You manage dietary requirements in three steps in advance. 1) Ask in the invitation: 'Do you have any dietary requirements or allergies? Let us know.' 2) Collect the answers in an overview: vegetarian, vegan, gluten-free, nuts, shellfish-free, kosher, halal or other. 3) Send this to the caterer together with the guest list, so they can plan their supplies. Watch for signals from the caterer. 'That's difficult' is a red flag, 'no problem, we know this well' a green one. Rule of thumb: 30% of your guests expect vegetarian options, 10% gluten-free and 5% vegan. Prevent incidents: serving staff visibly label what is vegetarian or gluten-free, with a small label. Provide separate cutlery and staff for nut allergies. Adjusting the quantity is usually possible up to five days in advance. Live Impact checks all dietary requirements two weeks beforehand.