bang (people's) heads together

To forcefully make two or more people act, behave, or think in way that is appropriate or necessary. We're so far behind because your team keeps procrastinating. You need to go in there and bang their heads together. She claimed she would go into the negotiations and bang everyone's heads together until a deal was reached. The CEO is pretty mad that you guys still haven't reached a decision about this. He said he's going to come down and bang your heads together if need be.

bang your/their/our heads together

To scold two or more people harshly. If you two do something this stupid again, I'm going to bang your heads together! The CEO is pretty mad that you guys still haven't reached a decision about this. I think he's gonna come down and bang your heads together. We're so far behind because your team keeps procrastinating. You need to go in there and bang their heads together.

bang (or knock) people's heads together

reprimand people severely, especially in an attempt to stop them arguing.

1998 Community Care There are few signs yet that the SEU has been willing to bang government heads together over social security policy.