If you simply guess how much meat you will need to feed all of your guests, chances are one of two things will happen. Either you will end up with too little, leaving your guests unsatisfied and hungry, or you will have leftovers. While the latter may not always be a bad thing, if you're trying to conserve money -- or room in your refrigerator -- you might prefer to buy just the right amount of meat. To do so successfully, you must figure out how much meat to buy per person you wish to serve.
Plan the entire menu for your event before you try to calculate how much meat you will need. If you change your mind about serving meat as an appetizer and decide to make it the main course, you will find that you are woefully short if you already have purchased meat based on your intent to use it as an appetizer. Making a detailed menu will help you minimise these last-minute changes and give you a better idea of how much meat you will need.
Use your menu to help you assess how big a portion of the meal meat will provide. For example, if you are serving a main course of meat that also includes pasta and a baked potato, you will not need as much meat as if you want to serve each person a steak -- and nothing else -- as the main course.
Multiply the number of guests you wish to serve by 0.2 if the meat is going to be an appetizer. Multiply the number of guests by 0.5 to 0.33 if the meat will be a part of the main course but there also will be other filling components. If you are going to mix the meat into another dish, such as a curry or chilli, multiply the number of guests by 0.25 to 0.33. If you intend to serve the meat as the centre of the meal with few -- if any -- accompaniments, multiply the number of guests you wish to serve by 0.75. This resulting number in these calculations will provide you with the number of pounds of meat you should purchase to feed your guests.