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The purposes of this study were (1) to explore empirical challenges in dimensioning safety buffers and their implications and (2) to organise those challenges into a framework.

In a multiple-case study following an exploratory, qualitative and empirical approach, 20 semi-structured interviews were conducted in six cases. Representatives of all cases subsequently participated in an interactive workshop, after which a questionnaire was used to assess the impact and presence of each challenge. A cross-case analysis was performed to situate empirical findings within the literature.

Ten challenges were identified in four areas of dimensioning safety buffers: decision management, responsibilities, methods for dimensioning safety buffers and input data. All challenges had both direct and indirect negative implications for dimensioning safety buffers and were synthesised into a framework.

This study complements the literature on dimensioning safety buffers with qualitative insights into challenges in dimensioning safety buffers and implications in practice.

Practitioners can use the framework to understand and overcome challenges in dimensioning safety buffers and their negative implications.

This study responds to the scarcity of qualitative and empirical studies on dimensioning safety buffers and the absence of any overview of the challenges therein.

The purpose of this study is to identify, characterize and assess supplier flexibility measurement practices in the order-to-delivery process.

The study involved a survey; participants were 224 purchasing managers at Swedish manufacturing companies that had more than 20 employees.

Scrutiny of the details of measurement practices revealed that most respondents actually do not specifically measure supplier flexibility. Instead they measure other measures like delivery reliability, conduct qualitative follow-ups, or cannot specify how supplier flexibility is measured. It was acknowledged that they measure different supplier flexibility aspects, and the applied measures were characterized, e.g. in terms of which flexibility dimension they represent.

Conceptual clarifications and adaptations to measuring supplier flexibility in the order-to-delivery process are provided. The identified measures can be a contribution in further developing literature on flexibility performance measurement.

Purchasing, logistics and supply chain managers in search of supplier flexibility performance measurement can find ways to measure and an extended flexibility vocabulary. This has the potential to improve flexibility in the supply chain.

Even though flexibility is claimed as being an important competitive advantage, few empirical studies and operationalized measures exist, particularly in the order-to-delivery process.

The purpose of this paper is to explain the effects of inherent differentiation and system level performance assessment in inventory management. This is done by comparing the performance of two common safety stock methods, by considering the methods’ inherent differentiation and item group-level performance effects.

Due to the lack of analytical relationships between the two methods, the analysis is based on event-driven simulations. Data are collected from eight different case companies. Findings explain the importance of assessing safety stock performance for groups of items and not for individual items, as is common in academic studies. It explains how the methods’ inherent differentiation and planning environment characteristics affect the relative performances of the two safety stock methods.

The study explains the importance of assessing performance of safety stock methods on a system-level, rather than on item-level measures. It explains why the demand fill-rate method has a negative impact on the performance for groups of items, while the number-of-days method has a positive impact. The study also explains how the group-level safety stock performance is affected by five demand data characteristics.

The study explains the importance of assessing performance of safety stock methods on a system-level, rather than on item-level measures. It explains why the demand fill-rate method has a negative impact on the performance for groups of items, while the number-of-days method has a positive impact. The study also explains how the group-level safety stock performance is affected by five demand data characteristics.

Understanding the necessity of system level assessment of safety stock performance, how methods inherently differentiate service levels, and how demand characteristics affect methods’ performance can guide the choice of safety stock methods in companies.

No research on the characteristics of the number-of-days safety stock method, any assessment of differentiation characteristics of and comparison with the demand fill-rate method, has been published. The variable “inherent differentiation” is also introduced and defined.

The purpose of this paper is to examine the inventory performance effect of advanced material planning modes and analyse how internal and external contextual difficulties moderate this relationship. This study also identifies avenues for future research.

The empirical analysis uses a survey of material planning for purchased items in 292 Swedish manufacturing and wholesaling companies. Three dimensions of inventory performance are dependent variables: material planning performance, inventory turnover rate, and service level.

Advanced material planning modes are directly associated with material planning performance, but this study could not verify direct associations with inventory turnover rate and service-level performances. External and internal contextual difficulties have direct effects on all inventory performance dimensions and moderate the inventory performance effect of advanced material planning modes. The moderating effect is stronger in non-difficult contexts, for which advanced material planning has significant inventory performance effects. Demand- and human-related contextual dimensions are especially critical.

The study identifies the following guidelines for companies to consider in order to unlock the potential of advanced material planning: consider full implementation of advanced material planning in non-difficult contexts; minimise the plan variability effects of high parameter revision and planning frequencies; minimise the need for, and use of, manual modification of planned orders before release; reduce demand uncertainty and variability; and secure appropriate human skills and working time.

This study somewhat contradicts the literature on material planning by not finding a direct positive effect on any inventory performance dimension from analytical design of order quantities and safety stocks. The research adds to the literature by identifying direct and moderating effects of external and internal contextual difficulties on all three-inventory performance dimensions. The relative importance of managing automatic order release identified in the study motivates future research as the effect has not been previously highlighted in the literature. Accordingly, avenues for future research and an agenda for practice-oriented research are suggested.

The purpose of this study is to develop a framework of strategies to achieving customer order flexibility in and related to the order-to-delivery (OTD) process. The purpose is also to investigate how companies prioritize various strategies to achieve customer order flexibility.

Based on a literature review, pre-tests and conceptual reasoning, a conceptual framework of strategies related to the order-to-delivery process was developed. The strategies were linked to the order quantity and delivery lead-time flexibility dimensions. This structure resulted in six groups covering enabling as well as remedial strategies. An empirical interview study of ten customer–supplier relationships was conducted.

The interviews identified additional strategies, thereby expanding the framework. The enabling strategies with the highest median values were “have continuous contact with the customer's purchaser” and “use safety stock of raw materials/semi-finished products”. The remedial strategy with the highest median was “re-plan/re-prioritize the order backlog”. In the delivery sub-process, it was more common to apply remedial strategies for delivery lead-time than for order quantities.

The developed framework is a contribution to the literature on operational flexibility in and related to the OTD process. It complements existing knowledge by taking a supplier perspective.

Suppliers can use the framework as a tool to understand and systematically achieve better customer order flexibility in and related to the OTD process. Customers can use the framework as a checklist for supplier evaluation and supplier development.

Few identified studies include empirical data on customer order flexibility.

Flexibility is one enabler of efficient use of resources and is therefore an antecedent to sustainability. The purpose of this article is to identify supplier flexibility variables in, and related to, the order-to-delivery (OTD) process and categorize them into a framework, followed by empirically exploring the framework.

A perception-based survey was sent to Swedish purchasing managers. 289 responses were received. After descriptive gap analysis, exploratory factor analysis was applied to structure the responses into factors. This formed the basis for hierarchical linear regression analysis, explaining supplier flexibility.

A conceptual framework, specifying supplier flexibility into volume, delivery and information exchange dimensions and relating these dimensions to the OTD process, was developed. Significant negative gaps between actual and demanded volume flexibility and delivery flexibility were identified, while positive gaps were found for information exchange flexibility. The factor analysis revealed three factors. The regression analysis verified that OTD-related information exchange flexibility and OTD-related volume and delivery flexibility explain the variation in OTD-specific flexibility and are important antecedents for supplier flexibility in the OTD process.

A contribution to research is the framework – with defined, related and empirically validated flexibility types.

The study proposes a perception-based way to capture supplier flexibility in the OTD process, which is of practical relevance when evaluating suppliers.

Identifying, conceptualizing and capturing types of supplier flexibility in the OTD process is new related to academic literature. Also the wide empirical study mapping supplier flexibility gaps is unique in its focus.

The paper seeks to describe the state‐of‐the‐art, reasons for selecting various material planning methods, and modes of applying methods for initiating inventory replenishment of purchased items. It also identifies trends from 1993 to 2005.

Empirical survey data are collected from Swedish manufacturing companies in 1993, 1999 and 2005. The MRP, re‐order point, fixed interval ordering, run‐out time, and Kanban methods are studied.

MRP is the most commonly used method and its position has strengthened since 1993. A common way of determining parameters such as order quantities and safety stocks is to use judgment and experience. Parameters used in material planning methods are reviewed relatively infrequently. The planning frequency has increased, with daily planning now being typical.

The major limitation is that different data collection techniques were used in 1993 compared with 1999 and 2005. An important research implication is that the state‐of‐the‐art applications differ from theoretically appropriate application modes. The trends are towards less appropriate modes among the most widespread applications.

The frequency of reviewing planning variables is relatively low in industry, and should in most situations be increased. The paper implies that more user‐friendly software applications need to be developed and implemented. It could serve as guidelines when designing and developing training and education programs and function as a benchmark.

The paper provides a longitudinal state‐of‐the‐art description of materials planning usage and identifies application modes with positive and negative performance impact.

The purpose of this paper is to generate a performance model for an order‐to‐delivery (OTD) process in delivery scheduling environments. It aims to do this with a triadic approach, encompassing a customer, a supplier and a logistics service provider.

The paper takes the form of a conceptual analysis and a triadic case study on performance measurement requirements in an OTD process characterized by delivery scheduling, and generating performance models.

Two OTD process performance models, one for the supplier's delivery sub‐process and one for the customer's delivery scheduling, the logistics service provider's transportation and the customer's good receipt sub‐process, in delivery scheduling environments are generated.

A single case study limits the levels of external validity and reliability to analytical generalization.

The generated performance models include definitions of four sub‐processes and outline ten performance dimensions that should be of relevance for several companies to apply.

This is the first approach that generates performance models for a triadic OTD process for use in delivery scheduling environments.

The applicability of manufacturing planning and control methods differs between environments. This paper explains the fit between the planning environment and material and capacity planning on the detailed material planning and shop‐floor planning levels. The study is based on a conceptual discussion and a survey of 84 Swedish manufacturing companies. Results show the use of planning methods and their levels of user satisfaction in complex customer order production, configure to order production, batch production of standardized products and repetitive mass production, respectively.

The objective of this study is to revise and enhance existing inventory control models in a way that allows them to be used more efficiently in environments with short lead times.

A simulation approach has been chosen to assess the efficiency of the developed model. This simulation is based on randomly generated demand data with a compound Poisson type of distribution.

Results from the simulation show that traditionally used inventory control methods fail to ensure that desired service levels are attained in environments with short lead times. The simulation also shows that, by using the developed model, the differences between desired and attained service levels can be reduced to fall within limits acceptable in practice.

The study provides an enhanced inventory control model that can be used in environments with short lead time to increase service level performance.