The Work Preference Inventory (WPI) is designed to assess individual differences in intrinsic and extrinsic motivational orientations. Both the college student and the working adult versions aim to capture the major elements of intrinsic motivation (self-determination, competence, task involvement, curiosity, enjoyment, and interest) and extrinsic motivation (concerns with competition, evaluation, recognition, money or other tangible incentives, and constraint by others). The instrument is scored on two primary scales, each subdivided into 2 secondary scales. The WPI has meaningful factor structures, adequate internal consistency, good short-term test-retest reliability, and good longer term stability. Moreover, WPI scores are related in meaningful ways to other questionnaire and behavioral measures of motivation, as well as personality characteristics, attitudes, and behaviors. Some people seem to be driven by a passionate interest in their work, a deep level of enjoyment and involvement in what they do. In describing the difference between successful and unsuccessful scientists, the Nobel laureate Arthur Schawlow remarked, "The labor of love aspect is important. The successful scientists ... are just impelled by curiosity" ("Going for the Gaps," 1982, p. 42). The novelist John Irving similarly explained his long, intense writing sessions: "The unspoken factor is love. The reason I can work so hard at my writing is that it's not work for me" (Amabile, 1989a, p. 56). Both the scientist and the writer describe their driving force as "love." By contrast, some people seem to be motivated more by external inducements in their work. Writing in her private journal, the poet Sylvia Plath attempted to understand her writer's block: "Editors and publishers and critics and the world.... I want acceptance there, to feel my work good and well-taken, which ironically freezes me at my work, corrupts my nunnish labor of work-for-itself-as-its-own-reward" (Hughes & McCullough, 1982, p. 305).
