1. Set up obstacles that will make your lunch hard to remove. This will let the bandit know you're on to him. Staple a brown bag shut or put a luggage lock on a zippered lunch tote, and double-wrap sandwiches and snacks in crackly aluminum foil or paper.
2. If the theft continues, hide some bells (available at craft stores) in the bottom of the bag so it jingles when moved. If you don't sit near the kitchen, do your best to stake out the area around lunchtime.
3. Once you've caught the culprit, resist the temptation to yell or accuse. Just say, "I believe that's my lunch," and let the guilt and humiliation do all the work. The thief is likely to call it a misunderstanding, but you'll both know the truth.
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