Business partnerships tend to end the way marriages do. Slowly, then all at once, with a moment where trust breaks and someone decides they’re done. The difference is that a business divorce doesn’t come with decades of family law precedent guiding every move. It comes with a company that still has customers, employees, bills, and a bank account, all sitting in the middle of two people who no longer agree on anything.

What you do in the first few days after that moment decides more than most business owners realize. Illinois law offers real remedies for owners who reach an impasse, buyouts, provisional directors, even court appointed custodians to keep a business running through a fight. But those remedies favor the owner who acted carefully, not the one who reacted first. Here are the five moves that tend to do the most damage before a lawyer ever gets involved.

1. Never Lock Your Co-Owner Out of the Business or Its Accounts