[Research action: a contribution to nurses' investigative practices].

The present paper shows a theoretical reflection on action research methodology as an alternative strategy to the conventional model of scientific investigation. Methodology is discussed from the perspective of two scholars who propose two different structural models: action-investigation cycle and flexible stage model. We provide examples of the use of action research from studies carried out by nurses. Action research is an emergent model which is being more and more adopted in educational and nursing fields, reflecting the necessity of deeper theoretical knowledge and revealing itself as a useful instrument in nursing research.