The foundational logic underpinning inventory management in many supply chains has historically been economic based, especially with respect to lean philosophy. The goal was to minimise holding costs, increase inventory turnover and rely on stable lead times (Christopher & Peck 2004). However, port disruptions challenge these assumptions by introducing irregular flow patterns, unpredictability in delivery schedules and bottlenecks that ripple through the supply chain. Under such conditions, minimising inventory can shift from a strength into a critical vulnerability. And suddenly, the carefully balanced system unravels. Shipments stall at congested ports because of labour strikes, equipment failures or natural disasters, causing unpredictable delays and extended transit times (Christopher & Peck 2004). This disrupts the JIT flow, leading to inventory shortages at critical points in the supply chain (Christopher & Peck 2004).

Manufacturers face production slowdowns, retailers experience stockouts and customers encounter unmet demand (Christopher & Peck 2004). The ripple effect escalates costs dramatically, including demurrage fees, expedited shipping charges and overtime labour costs as companies scramble to respond to logistic bottlenecks (Christopher & Peck 2004). Without sufficient safety stock reserves, the risk of lost sales and damaged customer relationships intensifies, forcing firms to rethink their lean inventory strategies and embrace higher inventory levels as a buffer against ongoing uncertainty (Christopher & Peck 2004). What was once an asset optimised for cost-efficiency suddenly becomes a liability that threatens the entire supply chain’s resilience and service levels (Christopher & Peck 2004).

Recent disruptions at the Port of Durban, including delays caused by infrastructural underinvestment, labour unrest and weather-related damage, have resulted in severe service and delivery disruptions (Transnet National Ports Authority 2023). This prompted South African retailers to reassess their inventory strategies. Rather than strictly adhering to lean principles, firms have begun incorporating resilience-focused practices. These include things like strategic hoarding, spreading out inventories over several sites and preparing depending on different scenarios.

People are now thinking about inventory to protect against unpredictability. This method is in line with the idea of ‘adaptive buffering’ in resilience literature, where inventory serves as a shock absorber that keeps service levels high even when there are problems upstream (Pettit et al. 2019). This signifies a fundamental transformation from perceiving inventory as waste to acknowledging it as a catalyst for continuity (Pettit et al. 2019).

There are several ways to build redundancy into inventory systems, such as having safety stock, having alternative supply sources or using more than one distribution centre. Ivanov (2021) says that these steps make the supply chain more complicated and expensive, but they are necessary to make it stronger. In South Africa, where there are not many other ways to get goods into the country and the country relies heavily on imports, redundancy is not just a good idea but also necessary.

Companies that have been able to get through Durban’s port problems the best prefer to keep goods in places farther away from the port. This means they do not have to rely on real-time replenishment as much. This method aligns with the research conducted by Hirsch et al. (2024), indicating Fast-Moving Consumer Goods (FMCG) businesses employing proactive redundancy planning achieved superior order fulfilment rates during peak interruption times.

There are trade-offs, though, when it comes to redundancy. It costs money to store it, tie up resources and risk it becoming obsolete. So, South African stores have started using selective redundancy methods, focusing on goods with high margins and fast sales. Inventory modelling tools have become vital in determining optimal stock levels, helping firms balance the costs of holding inventory against the risks of stockouts.

Inventory subdivision is putting items into groups based on how important they are, how much demand they have and how profitable they are. Then, you use various resilience tactics for each group. For instance, vital commodities may need more safety stock and a wider range of sources, whereas non-essential goods would need less. This is like what Du Plessis et al. (2022) found: that container imbalances on export routes need a selected approach to inventory planning.

South African businesses might better prioritise their limited resources using segmented inventory systems. This frequently means putting extra effort into making sure that stock-keeping units (SKUs) that have high substitute prices or a big effect on reputation are not lost. It also makes it easier to align inventory choices with the company’s overall risk appetite.

Effective inventory resilience depends critically on visibility of stock across the supply chain (Pettit et al. 2019). Visibility enables firms to make informed decisions on safety stock deployment, lead time adjustments and risk mitigation (Ponomarov & Holcomb 2009). However, many South African retailers operate with fragmented Information and Communication Technology (ICT) infrastructure and limited digital integration, particularly among SMEs (Ngcobo & Naudé 2022). This impedes access to real-time inventory data and undermines scenario-based planning. Without visibility, redundancy strategies risk becoming inefficient, as firms cannot accurately align buffer stock with disruption-prone nodes (Hirsch et al. 2024). Thus, inventory visibility is not optional but foundational to achieving supply continuity in volatile logistics environments.

The movement towards resilient inventory management also involves greater reliance on risk-based decision-making tools. Scenario analysis, simulation and stress testing are increasingly used to anticipate disruption impacts and evaluate mitigation options. Daneshvar Kakhki and Gargeya (2019) explain that these tools enable firms to quantify the trade-offs between cost efficiency and resilience.

For example, probabilistic models help firms estimate the expected loss from stockouts versus the cost of carrying additional inventory. This enables more informed and strategic decisions rather than reactive responses. In South Africa, where port delays are semi-systemic, companies benefit from integrating risk scenarios into their monthly or quarterly inventory planning cycles.

Inventory resilience is not purely a technical matter. It also involves organisational behaviour. Firms that promote cross-functional collaboration between procurement, logistics and finance departments tend to coordinate resilience efforts more effectively. Agigi et al. (2016) emphasise that resilient supply chain design in South African FMCG companies often stems from leadership commitment to agility and responsiveness.

Transforming organisational culture around inventory from a cost-obsessed mindset to one oriented towards continuity requires internal education and incentive realignment. Inventory managers must be empowered to make buffering decisions based on risk assessments rather than solely on historical consumption data. This cultural shift is especially critical in sectors characterised by high demand variability or long lead times.

Perhaps, the most complex challenge in adopting redundancy-based inventory strategies is justifying the associated costs. Inventory is capital intensive and increases balance sheet exposure. However, Sheffi and Rice (2005) argue that investments in resilience should be viewed as options that protect the firm from substantial downside risks. This perspective is gaining traction in the South African retail sector, particularly following the COVID-19 pandemic and the 2021 civil unrest, both of which triggered widespread supply disruptions (Vhumbunu 2021).

Retailers are increasingly recognising that the cost of not having inventory when needed, lost sales, reputational harm and operational downtime, can far outweigh the costs of holding extra stock. Nevertheless, the scale and nature of these trade-offs vary widely depending on firm size, sector and customer base, necessitating customised strategies.

Studies from 2013 onwards have traced the shift from lean inventory principles to resilience-oriented models in response to rising disruption frequency (Agigi et al. 2016; Magagula et al. 2020). South African research reflects this trend in the context of port unreliability and constrained infrastructure (Du Plessis et al. 2022; Vhumbunu 2021). Inventory redundancy, previously deemed inefficient, is now cited as a resilience mechanism under systemic risk (Hirsch et al. 2024; Ivanov 2021). Scholars also emphasise digital visibility as a foundational enabler of responsive inventory systems (Daneshvar Kakhki & Gargeya 2019; Ngcobo & Naudé 2022).

Consequently, the literature offers the essential conceptual framework to investigate SCRT more comprehensively. The evolution of inventory strategy has been influenced by persistent issues at ports, both practically and theoretically. This research establishes the foundation for subsequent sections that will explore the theoretical foundations of SCRT and present a comprehensive resilience framework tailored for the South African environment.

The intellectual underpinnings of SCRT originated in the early 2000s, influenced by significant global disruptions such as the 9/11 terrorist attacks, the 2002 West Coast port lockout in the United States and the SARS (severe acute respiratory syndrome) epidemic, which commenced in November 2002 and continued until 2004 (Sheffi & Rice 2005). These calamities revealed the weaknesses in global supply systems that emphasised efficiency above resilience (Ponomarov & Holcomb 2009). Christopher and Peck (2004) provided one of the earliest formal definitions of supply chain resilience, describing it as a complex capacity that includes agility, cooperation, visibility and redundancy (Mara & Mokoena 2024).

Their concept acknowledged resilience as a developing result of inter-organisational collaboration and proactive risk detection, rather than merely a product of internal capability. This first inquiry laid the groundwork for further empirical research. Subsequent studies have examined various resilience facilitators, such as the function of enterprise systems (Daneshvar Kakhki & Gargeya 2019), dynamic capabilities for risk adaptation (Dubey et al. 2021) and the application of digital technologies to improve real-time responsiveness (Hirsch et al. 2024; Mara & Mokoena 2024).

Supply chain resilience theory emphasises that resilience stems from capability development across three temporal phases: Readiness, Response and Recovery (Pettit et al. 2019; Sheffi & Rice 2005). These are enabled by four core constructs namely:

These constructions are interdependent and mutually reinforcing. Together, they constitute what Ponomarov and Holcomb (2009) describe as a ‘resilient supply network’. They reflect a systemic orientation where resilience emerges from dynamic interplays between capabilities, rather than isolated investments in individual practices.

Scholars noted that the application of SCRT has been validated in manufacturing, retail and logistics through qualitative and quantitative research. Ivanov and Das (2020) utilised simulation modelling to assess the effects of supplier diversity, inventory buffering and lead time flexibility on resilience during pandemic-like disruptions. Their findings demonstrated that supply chains marked by redundancy and agility are more proficient at absorbing shocks and facilitating quick recovery, hence validating SCRT’s emphasis on dynamic capabilities and system flexibility. The study by Tsolakis et al. (2023), discovered that inter-organisational coordination accelerates recovery amid significant uncertainty in a multi-tier cooperation. These findings corroborate SCRT’s core, which argued that resilience is derived from strategically aligned skills, such as visibility, redundancy and collaboration (Pettit et al. 2019; Sheffi & Rice 2005).

In South Africa, evidence highlights the importance of SCRT in emerging markets. Magagula et al. (2020) found that merchants mitigated port disruptions by utilising decentralised inventory systems and warehouse redundancies. Agigi et al. (2016) observed a rising implementation of safety stocks and supplier diversification in the FMCG sector. Supply chain resilience theory has also been combined with other frameworks. Dubey et al. (2021) integrated it with dynamic capacities theory, associating resilience with organisational learning and creativity. Mubarik et al. (2021) demonstrated how SMEs modify SCRT concepts to fit resource-limited environments, customising tactics to align with operational realities.

Even if people use SCRT, it is criticised for making normative assumptions and suggesting ideal behaviours like agility and visibility without taking real-world limitations into account (Wieland & Durach 2021). These kinds of talents frequently rely on modern ICT infrastructure, which is not very common in many underdeveloped nations. Digital skills in South Africa’s industrial sector are not evenly distributed and are not getting enough money (Ngcobo & Naudé 2022).

Supply chain resilience theory also implies that many companies don’t have flexible resources. SMEs frequently lack the resources, negotiating leverage or authority to execute redundancy or cooperation successfully. For instance, South African SMEs have trouble exchanging information and integrating platforms because their digital ecosystems are broken and there are power inequalities (Weber & Badenhorst-Weiss 2018).

Also, SCRT generally does not consider limitations in institutions and infrastructure. To make South Africa more resilient, the government must change the rules, invest in infrastructure and work together with businesses (Magagula et al. 2020; Ngcobo & Naudé 2022). In the absence of such measures, concepts from industrialised markets may be ineffective in regions characterised by unreliable transportation, insufficient supervision and informal economies (Ivanov 2021). In such circumstances, resilience often derives from informal networks, indigenous knowledge and grassroots solutions that surpass conventional SCRT models (Magagula et al. 2020).

The strategic layer includes setting up the supply chain, choosing partners and making rules. The Port of Durban in South Africa is a good example of how fragile concentrated port dependency can be. There are problems with congestion, cybersecurity and labour unrest (TNPA 2023; Vhumbunu 2021). Retailers are implementing varied port entry and inland hub strategies (Du Plessis et al. 2022), in accordance with Blos, Wee and Yang’s focus on adaptability and redundancy. Strategic resilience necessitates public-private partnerships and collaboration with government entities, port authorities and industry organisations to facilitate regulatory reform and infrastructure investment (Loury-Okoumba & Mafini 2018; Magagula et al. 2020).

Resilience skills at the operational level include managing inventories, making sure that supply and demand are in sync and being able to change modes of transportation. To protect themselves from interruptions, South African stores employ decentralised inventories and a variety of suppliers (Magagula et al. 2020). Safety stocks, which used to be thought of as wasteful, are now very important safety measures (Agigi et al. 2016). Internet of Things (IoT) sensors and Artificial Intelligence (AI) tracking help with operational visibility, which speeds up response times when things go wrong (Hirsch et al. 2024). However, many businesses use a mix of manual and digital systems as they do not have enough resources. Flexibility in logistics, such as being able to route through Port Elizabeth or Maputo instead, shows how dynamic adaptation works (Christopher & Peck 2004). Scenario-based inventory reallocation and flexible logistics contracts enhance operational resilience.

The tactical layer is all about being able to act quickly through competent workers, good communication and processes for responding. In South Africa, where there are a lot of informal jobs and skill shortages, it is very important to teach frontline personnel to spot early warning signals and act on their own (Magagula et al. 2020). A ‘redundancy culture’ (Dubey et al. 2021) sees extra capacity and safety supplies as strategic needs instead of waste, which needs strong leadership backing. Timely communication among warehouses, transit providers and suppliers expedites recovery, in accordance with the restorative capability of SCRT (Ponomarov & Holcomb 2009).

The study draws on an extensive review of peer-reviewed articles from reputable academic outlets such as the Journal of Transport and Supply Chain Management and Acta Commercii, alongside global resilience literature. It synthesises theoretical developments in SCRT, inventory management and the effects of port disruptions. The layered resilience framework of Blos et al. (2012) forms the foundation for conceptual analysis, adapted through cross-referencing with empirical case findings to ensure relevance to emerging markets.

The selection of the Blos et al. (2012) layered resilience framework is justified by its multi-tiered structure, which distinguishes between strategic, operational and tactical capabilities. This stratification is particularly appropriate for the South African retail environment, where disruption occurs simultaneously at infrastructural, organisational and executional levels. Unlike linear resilience models, the layered approach accommodates systemic port fragility, governance constraints and firm-level inventory decisions within a single integrative architecture.

To visually reinforce this conceptual foundation, Figure 1 and Figure 2 align with the layered model, demonstrating how SCRT constructs map across resilience phases and operational realities in the South African context.

Figure 1 depicts the foundational constructs of SCRT, highlighting the four core capabilities that enable organisations to withstand and recover from disruptions. These capabilities include redundancy, agility, visibility and collaboration.

Figure 2 presents an adapted resilient supply chain structure based on the layered resilience framework proposed by Blos et al. (2012), contextualised for environments characterised by persistent port disruptions. The model illustrates how structural, operational and relational resilience mechanisms interact to support supply chain continuity.

Chronic interruptions at the Port of Durban offer concrete examples that support the study’s arguments. The article looks at real-world problems and the techniques that merchants use to deal with them by using secondary sources, industry studies, government publications and news coverage of things like traffic jams, labour strikes and cyberattacks. These examples show how current resilience theories can be used and how they cannot be used when there are operational restrictions. These cases were selected for illustrative purposes because they represent a range of South African retail firms directly impacted by port congestion, providing practical insights into operational resilience under disruption.

A critical lens aligns theoretical ideas with empirical practices, assessing normative prescriptions in relation to actual behaviours. Using more than one source of literature and real-world examples makes the results more reliable. Although it lacks quantitative confirmation, this approach enables in-depth theoretical analysis tailored to the challenges of South African logistics.

Secondary sources were included if they were published between 2013 and 2024, focused on inventory resilience or SCRT and provided relevance to South African retail or port operations. Excluded sources were geographically irrelevant or pre-2013 without enduring theoretical value. Data synthesis followed a thematic approach, with cross-comparison between literature and illustrative case reports (industry publications, news reports, government data). Case studies were selected to represent different firm sizes and supply chain configurations within the Durban port context, enabling triangulation of findings.

Repeated disruptions at the Port of Durban have triggered a shift from lean, centralised, JIT systems to strategies incorporating deliberate redundancy (Du Plessis et al. 2022; Vhumbunu 2021). Measures include increased safety stock, multi-echelon positioning and decentralised distribution centres to improve buffer stock (Sheffi & Rice 2005).

‘A logistics director noted: “Holding more stock is expensive, but running out during peak season was devastating”’. Proactive stock positioning in inland warehouses allowed some firms to sustain fulfilment despite a 3-week clearance delay (Hirsch et al. 2024). Successful approaches applied redundancy selectively, prioritising high-margin or high-velocity SKUs, guided by simulations and scenario planning (Ivanov & Das 2020; Tsolakis et al. 2023).

However, SMEs faced challenges implementing adaptive redundancy as a result of limited capacity and weak supply node visibility (Magagula et al. 2020). While cost remains a concern, many now view inventory as a strategic continuity asset, aligning with resilience theory’s emphasis on preparedness over efficiency (Pettit et al. 2019). SMEs often lack financial resources, digital infrastructure and logistics capacity to implement full SCRT-based strategies. Adaptations include reliance on selective redundancy, simplified ICT tools and collaborative arrangements with larger firms or local transport providers. These adjustments allow SMEs to achieve partial resilience while acknowledging resource limitations and operational constraints.

The supply chain resilience theory’s focus on redundancy, visibility and collaboration (Blos et al. 2012; Ponomarov & Holcomb 2009) is relevant but constrained by emerging market realities, including infrastructural decay and institutional volatility (Ngcobo & Naudé 2022).

Key limitations include the assumption that firms can easily reconfigure supply chains, difficult in contexts with poor rail links, congested secondary ports and fragmented logistics (Weber & Badenhorst-Weiss 2018). Digital integration is also hampered by unreliable ICT and siloed data. One executive called full visibility ‘ideal but utopian’ under current conditions (Hirsch et al. 2024).

Resilient firms adapted SCRT locally by creating micro-resilience units, categories, regions or supplier-specific cells able to function and recover independently (Christopher & Peck 2004; Ivanov 2021). This modular approach favours strategic segmentation over wholesale reconfiguration.

Supply chain resilience theory’s emphasis on iterative learning was validated: firms that endured COVID-19 lockdowns and 2021 unrest had stronger contingency planning and faster recoveries (Dubey et al. 2021). Lessons from past crises were embedded into operations, confirming resilience as an evolving capability (Taleb 2012).

Table 1 maps SCRT constructs to South African operational realities.

With over a decade (2013–2024) of peer-reviewed research considered, the literature review synthesises key contributions on inventory strategy and supply chain resilience in disruption-prone logistics, with emphasis on visibility, redundancy and agility. Sources include: The Journal of Transport and Supply Chain Management, Acta Commercii, The International Journal of Logistics Management, and MIT Sloan Management Review.

The review targeted empirical studies, SCRT-based frameworks and conceptual works on visibility, redundancy, agility and collaboration; outdated or geographically irrelevant works were excluded. From 21 selected papers, four constructs emerged as foundational to inventory resilience, agility, collaboration, visibility and redundancy, mapped to SCRT’s readiness, response and recovery phases.

While scholarly consensus affirms these capabilities’ importance, most frameworks were designed for stable, resource-rich environments, underscoring the need for localised adaptations in fragile logistics networks like those surrounding Durban’s port.

As illustrated in Figure 3, the emergent SCRT constructs and inventory resilience strategies are categorised to highlight their conceptual and practical interrelationships. The resilience capabilities of agility, collaboration, visibility and redundancy represent key organisational mechanisms that strengthen supply chain resilience. These capabilities contribute to the broader SCRT phases of readiness, response and recovery, which collectively describe how organisations prepare for, respond to and recover from supply chain disruptions (Blos, Da Silva & Wee 2018). Together, these interacting elements form the foundation of inventory resilience, enabling retailers to maintain operational continuity and mitigate the effects of disruptions such as port congestion.

Figure 4 synthesises the key themes emerging from the analysed literature and aligns them with relevant phases of SCRT. Four dominant resilience capabilities were identified: agility, collaboration, visibility and redundancy. Agility reflects the speed and flexibility with which organisations reconfigure supply chains during disruption, supporting the response phase of resilience (Christopher & Peck 2004; Ivanov & Das 2020). Collaboration emphasises inter-organisational coordination and joint resilience planning, strengthening readiness capabilities (Dubey et al. 2021; Tsolakis et al. 2023). Visibility highlights the importance of real-time information sharing and digital integration to support both readiness and response, enabling firms to anticipate and manage disruptions more effectively (Hirsch et al. 2024; Ngcobo & Naudé 2022). Finally, redundancy represents the intentional maintenance of surplus resources, such as additional inventory, suppliers or logistics capacity, which supports recovery by allowing organisations to restore operational stability following disruptions (Blos et al. 2012; Sheffi & Rice 2005). These themes illustrate how resilience capabilities interact across different phases of supply chain disruption management.

Together, these dimensions frame how inventory strategies should be reconfigured to mitigate the risks associated with chronic port disruptions, particularly in emerging markets like South Africa. Table 2 categorises the literature accordingly.

Table 2 presents peer-reviewed studies mapped to SCRT phases, supporting our analytical framework. It reveals a growing empirical interest in operationalising SCRT constructs to enhance inventory resilience, particularly in disruption-prone markets. While early literature focused heavily on redundancy (e.g. Christopher & Peck 2004; Sheffi & Rice 2005), more recent work integrates visibility and agility as crucial enablers of timely response (e.g. Hirsch et al. 2024; Ivanov & Das 2020). Collaboration, though less frequently addressed, is emerging as a prerequisite for multi-tier resilience, particularly through supplier integration (Agigi et al. 2016; Tsolakis et al. 2023). Notably, few models are tailored to the South African port context, where infrastructural and institutional risks co-exist. This gap underpins the rationale for this journal article, which revisits the Blos et al. (2012) framework and proposes a modified, layered model aligned to both SCRT and local retail conditions.

The findings are not widely generalisable; subsequent studies should employ empirical approaches to validate and implement recommended models. Despite this, this method fills in gaps in the literature by bringing to light the realities of developing markets that are generally ignored in conventional resilience research.

Limitations include the conceptual nature of the study, reliance on secondary sources and focus on illustrative cases rather than full-scale empirical testing. Generalisability is limited to similar emerging market contexts. Future research should pursue empirical validation, quantitative modelling of cost-resilience trade-offs, longitudinal studies on adaptive learning and investigations into SME-specific adaptation of SCRT constructs.

Future research should focus on: