In forming your group, you should be looking for people with a particular set of skills. Look for those with backgrounds in the following areas: Medical (doctor, nurse, EMT), Security (military, police, special security), Communications (military, Ham), Food (specifically someone who understands diet, nutrition, and rations; water is included in this area), Mechanical (look for someone who can work on both new and late model vehicles). If you are fortunate enough to know people in these fields, great! If not, get volunteers for training in these areas. Once you have these people in place, start cross training. Everyone in your group should have a basic working knowledge of each field.