Decisions

effectively take decisions

You may not know yet the decision you need to take; work them out in a meeting.

Poll

for small, fully understood problems

Let the majority win.

Potentially save the acceptance rate in the form of coloured dots, to be able to come back to it later if necessary.

for complex problems, small groups

Let the best argument win.

Hand out problem beforehand, and allow members to work out arguments. Let neutral present the arguments to disconnect them from the person.

for unimportant problems, small groups

Talk until consensus is reached, potentially reaching a win-win.

for complex problems

Refine solution until no more arguments against it can be brought up.

You may structure the process like this:

Present proposition
Answer questions
Gather reactions from everybody
Potentially refine proposition
Ask everybody for any counter arguments; if found, refine again; else accept the proposition

for complex decision, weak leadership

Let team to take decisions fully, but use veto if something goes "wrong".

for unimportant problems, small groups

Choose solution which provokes the littlest resistance / negative feelings.

for complex problems, big groups

Choose someone to investigate and then take an informed decision.

You may structure the process like this: