Implement personal allowances but do not allow skimming or borrowing.

Personal allowances for the adults in the family can really help to maintain a family budget. If both adults know they have $X that they can use as they wish with no supervision it can be a real release to help keep all other spending in check. Borrowing is a battle that's hard to come back from. If one adult borrows from the family for a want, it may cause all sorts of extra stresses and feelings. Skimming is taking money without it being seen through other avenues of spending. Getting $20 cash back with the groceries and not being honest about it. If you're honest it's part of the allowance but dishonesty hurts everyone.