Critical incidents connected to nurses' leadership in Intensive Care Units.

Objective:: The goal of this study is to analyze nurses' leadership in intensive care units at hospitals in the state of São Paulo, Brazil, in the face of positive and negative critical incidents.

Method:: Exploratory, descriptive study, conducted with 24 nurses by using the Critical Incident Technique as a methodological benchmark.

Results:: Results were grouped into 61 critical incidents distributed into categories.