Objective: to investigate studies about software processes looking for practices which can be used to obtain agility in software processes. Method: A systematic review including seven search engines was executed in Feb/2010. To apply the defined criteria to select papers and extract information regarding working practices bringing agility to software processes. Results: from 6696 retrieved papers, 441 were selected to support the identification of 236 occurrences of 51 distinct practices associated with the concept of agility. Their descriptions were deeply analyzed and consolidated. After discarding those which appeared in the technical literature in a small amount of papers, 17 agile practices were identified. Conclusion: although further studies are necessary to evaluate the efficacy of these 17 agile practices, 12 of them have been more commonly approached in the software projects and could be primarily considered: test driven development, continuous integration, pair programming, planning game, onsite customer, collective code ownership, small releases, metaphor, refactoring, sustainable pace, simple design and coding standards.