Although suicide assessment has been researched, nurses haven't been included in studies nor has this been explored from a phenomenographic perspective. Suicide assessment by nurses was investigated using a phenomenographic design. Data were collected through observations, vignettes, and interviews. Phenomenographic analysis discovered four qualitative differences in suicide assessment among nurse participants: reliance on (1) examples of other suicide cases, (2) intuition, (3) others' assessments, and (4) prior experience. The categories were classified into a three dimensional theoretical structure of suicide assessment: (a) Knowledge, (b) Method, and (c) Reference. Variability in participants' assessments established a structure of suicide assessment that furthers understanding of how nurses assess suicide and provides implications for practice.