Cancer care professionals work in a stressful environment, but it is not clear what factors contribute to this stress. We surveyed 60 oncology personnel on an inpatient unit and a palliative care unit regarding levels of perceived work stress and its potential contributors. Logistic regression analyses were performed to determine predictors of staff stress. A total of 63% of staff reported experiencing ``a great deal'' of stress at work, which was predicted by greater perceived workload (odds ratio = 32.2; P < .0001), insufficient time to grieve patients' death (odds ratio = 9.75; P = .0007), lack of institutional support (odds ratio = 0.16; P = .009), perceived lack of resources (odds ratio = 0.06; P = .007), and lack of control over the choice of workplace (odds ratio = 0.10; P = .03). Measures to address work-related stress should be included in the planning of cancer programs.