Market diversity, consumers' increasing need for new and improved products, and aggressive competition have propelled flexibility to the status of critical factor in a successful manufacturing strategy. Nevertheless, most manufacturing organizations have not measured and assessed flexibility in a systematic way. The culprit may be the complexity involved in defining flexibility. There are many types of flexibility which are believed to be related in a hierarchical fashion. According to this popular perspective, resource (machine, labor, and material handling) flexibility supports flexibility at the shop floor level (routing, operation) which, in turn, enables flexibility at the plant level (mix, expansion, volume, modification, and new product) in order to promote overall manufacturing flexibility (Koste and Malhotra, 1999; Slack, 1987). This view establishes that labor flexibility lays the foundations for the flexibility pyramid. Despite this fact, there is, to date, no empirical study focusing specifically on the concept of labor flexibility (Vokurka and O'Leary-Kelly, 2000). This field survey attempts to fill this gap by identifying the individual, organizational, and job variables that contribute to labor flexibility. In doing so, it places a particular emphasis on the sound measurement of this outcome variable and proposes useful strategies to foster its development.
The printed circuit board (PCB) industry is considered well suited to conduct flexibility research. PCBs are made-to-order according to customers' specifications. The components used vary greatly in terms of shape, technological sophistication, and processing requirements. The ability to respond quickly to ever-changing customer demand is deemed essential for success in this industry (Suarez et al., 1996). Accordingly, this study was conducted in a PCB assembly plant using a variety of advanced manufacturing technologies (AMTs) for several types of processes. Components were placed on a board using surface-mount technology or through-hole placement. Following this process, the boards were inspected and sent to the press fit department where connectors were added to the boards. The boards were then subjected to a series of tests before going through the final assembly stage during which labels, keys, stiffeners, and insulators were installed onto the boards. This firm was also chosen because it was an independent contractor. As explained by the operations manager, any type of order from any customer could be expected at any time. Finally, worker transfers within departments and, to a lesser extent, across departments, promoted the development of labor flexibility. Special attention was devoted to the measurement of labor flexibility at the individual level.
Flexibility evokes the ability to cope quickly with changing circumstances or environmental uncertainty (Gupta and Goyal, 1989). As such, this manufacturing capability enables firms to adjust to shifts in customer demand (Gerwin, 1993). As traditionally standard products (e.g. automobiles, jeans) become increasingly customized, a wide range of options and a quick response to change have emerged as qualifiers for competitiveness. Flexibility is a multi-faceted concept. Several popular taxonomies shed light on this plurality and usually identify the following types: machine, labor, material handling, routing, operation, expansion, volume, mix, new product, and modification (D'Souza and Williams, 2000; Sethi and Sethi, ...