Although there has been significant research into coping with work stress, support mobilization has been largely overlooked. When workplace stressors adversely influence employees, they often turn to colleagues and supervisors for feedback and support. This article outlines the development of a new multidimensional measure of support mobilization: the Support Mobilization for Work Stressors (SMWS) inventory. Two studies revealed that the SMWS inventory shows evidence of reliability, factor structure dimensionality and replication across samples, convergent and discriminant validity with a perceived available support measure, and criterion-related validity with organizational outcomes. The 12-item inventory is rated with reference to three sources of support (supervisor, colleagues, non-work people), and assesses how often an employee has approached each of those sources to obtain four supportive functions (emotional, informational, instrumental, appraisal); thus producing 12 distinct support mobilization constructs.