Consensus is a decision making style that reflects the ideas and thoughts of all team members. Reaching consensus helps ensure that decisions are explored thoroughly and that strong disagreements have been resolved.
Although everyone in the group may not agree that the decision reached is the best solution, they can support the decision. To reach consensus, major differences of opinion in the group must be addressed. When the pooling of and exploration of ideas is desirable, reaching consensus may enable the group to achieve a higher quality decision. As consensus requires time, the appropriateness of its use must be weighed against the importance of the decision to be made.
Nominal Group Technique, Multi-Voting techniques and Criteria/Prioritization Matrices are very structured ways to help reach consensus. (click on the image to take you home)