The 3s Spreadsheet Test (3S Test) is a cancellation test with high stimulus density and low target-to-distractor ratio, to assess stimulus-centered and viewer-centered spatial neglect. Twenty-five stroke survivors with left-sided neglect and 68 age-matched healthy controls took the 3S Test. Patients also took the Apples Test, a validated cancellation test. No patient's accuracy on the 3S Test was in the normal range. A total of 91.7% of the patients had an abnormal start; 52.6% of the patients took abnormally long time to complete the 3S Test. The 3S and Apples Tests agreed poorly on both the viewer-centered and stimulus-centered neglect classifications (κ = .25 and .05, respectively), but consistently identified 8 of the 25 patients (32%) as having both forms of neglect while each isolated form of neglect was present in one patient (4%). Lesion data were consistent with previous studies. These findings suggest that the 3S Test is a sensitive cancellation test for assessing viewer-centered and stimulus-centered spatial neglect. We are currently developing the 3S Test version 2 to refine the test stimuli and the scoring procedure.