The odds of survival are compounded by belonging to a team. Any team that is not actively growing will lose effectiveness as it loses personnel. A group could theoretically be large enough to reach self-sufficiency by normal reproduction, but most groups will increase in size by bringing in new members. This is called recruiting.
After the apocalypse happens, civilization will become drastically different from what it currently is. The differences may seem large, but people still have the same basic needs; they need to eat, people still get sick, and there still needs to be some form of order. Because of this, there are a wide variety of tasks necessary to form a functioning society.
When recruiting, loyal, competent, intelligent people are desirable. Also look for those with valuable resources. Also try not to let people in who don't contribute anything or could be a drain on resources.
The most important aspect of an individual is versatility. People must be willing to do anything they can to help a newly formed group survive and thrive. All groups planning to survive long-term must have an organized system. Many components that should be included in this system are listed below.
These are not always selected, but a good chain of command led by a commander should be able to keep everything in check. They need to be good tacticians in dealing with both zombies and bandits. It may make them unpopular and possibly marked men, but commanders need to lay down the law and keep their nerve in stressful times. Commanders normally are the founders of the refuge or former military officers.
The lead position is something that can be easy to covet, but it is often unclear where the true power lies. It is not advisable to seek power, as internal squabbling will only destroy the effectiviness of the team. An effective leader must have leadership aptitude, logistical planning skills and good interpersonal skills.
An effective group will have well established lines of authority. Everyone should have a voice, but it must be brutally clear to everyone when to speak. Advisors are also valuable in replacing the leader if neccesary.
When dealing with people of lesser authority, it can be tempting to lead by a display of force. This is not always preferable, as fear can lead to hate, rather then the respect a group needs to function well. Fear is a powerful tool, but can quickly turn against the leader if misused. That said, a leader must not be afraid to assassinate, or brutalize when neccesary.
Specialized persons should focus on educating others as well as themselves, so that, if they are killed, others may take their role immediately.
Prior knowledge in communications can be valuable, whether it deals with two-way units, ham, or other system. These specialists would be constantly trying to contact any survivors or trying to see if any governing body, should one remain, be planning a rescue or a city "cleansing". They are also in charge of keeping track where the scouts are located and report to the community about upcoming events or emergencies.
In any society, the sick and injured need proper treatment. Everyone should know first aid and other life-saving techniques, but a professional would be advisable. Infections spread quickly to hospitals, and this profession may become scarce. Although one cannot afford to be picky, it is preferred to have medics or general practitioners than a chief executive.
Other forms of doctors will be necessary. Vets can help injured or sick animals, psychiatrists can help keep people in good mental health. Even scientific doctors will help store knowledge, although this is more useful in the aftermath.
Explosives are a powerful force, and several people should be made proficient in manufacturing and operating such weaponry for when needed. In the wrong hands, explosives can be extremely dangerous.
Non-combatants put "civil" in civilization. Yet in a world ruled by the undead, there is no neutral, so it is best everyone is trained to kill, even if it is not their primary purpose.
Scavenger or Scout
Good scavengers are quick, quiet, and observant, and are more useful in the city than in the country. They will need to know vital locations of their designated areas like shortcuts, choke points, dead ends, and more. Scouts and scavengers plan their routes to and from their destinations ahead of time, check buildings for supplies, get said supplies without being noticed as much as possible, look for other survivors, and come back to camp with goods for the fellow survivor.
Keep scavenger groups small, such as groups of three to six, so they don't attract too much unwanted attention. Make sure they are fit enough to carry a large load of supplies, run from danger, or engage in hit and run conflict. Former players of running sports and those who are quick on their feet are excellent for this role.
Tradesmen include a lot of different professions. Plumbers, carpenters, gunsmiths, builders, Shoemakers. A plumber is considered more valuable than a CEO because they know how to construct things and make sure they don't fall apart (World War Z). Without them, building shelters or transporting fresh water around will be difficult.
If a settlement has a gunsmith, they will have to give him supplies to build guns. Any kind will do. If he succeeds, they can arm themselves better. It would also be wise to stock up on ammo by scavenging, looting, raiding, or just plainly making them from what they have.
As bullets begin to run out and the focus leans on more traditional weaponry, a blacksmith, though rare in modern society, will be extremely useful in forging knives, spears and swords, as well as armour to further protect its people from dying at the hands of the living dead.
Engineer or Mechanic
An engineer keeps a well-organized group out of trouble. Engineers can fix and maintain generators, radios and vehicles. It proves to be an incredibly valuable profession. Although, an engineer is only useful if he has the parts and tools to do what the settlement needs.
Shop Keeper or Supply Manager
When in a moderately large or larger group, people need to set up a form of rationing to save supplies. In this situation, it is best to take a Socialist aproach in which all members are given the same rations if they are pulling their weight. This does not mean to refuse any supplies to a member who is unable to provide supplies or has had a run of bad luck, however. It is suggested that this is a side job for someone who is trustworthy and fair, as well as knowing simple math. These people could end up being some of the most important in a colony, as they can regulate how much people take.
Cook or Chef
Food is a necessity and cooks and chefs are the ones who prepare it for safe consumption. It is likely that ways of cooking, such as boiling or fire cooking, will be used, so deep frying and other methods of cooking that require now expensive luxuries will have little use. Good food, rare in an apocalypse, will also help raise morale.
Cooks also know what kind of food can keep everyone in shape and always have good condition, which everyone would welcome.
Being an interpreter is an important role if a group traveling in foreign lands, where it is not clear if native survivors speak their language.
This is another important role in foreign lands. Knowledge of the land, environment, zombie population and potential hazards can prove essential.
An important role if your team is in a rural area. An outdoors man has extensive knowledge in the outdoors and specializes in hunting, fishing, trapping, camping, general survival, and knowledge of weapon usage.
Someone who has extensive knowledge in horticulture, animal husbandry, and use of agricultural vehicles and equipment is a must for any long term survival teams who have enough room in their base for such a feat. Farmers know how to grow and manage crops and control livestock. They know the soil, what can grow, how much water it will need, and much more. Without farmers or knowledge on how to grow food, supplies will run out, and scavenging will not always help keep survivors nourished. It is best to learn these skills prior to the inevitable outbreak. It is a highly time-consuming but rewarding option to minimize the dangers outside the base.
Electrical Engineering Expert
This is an important role if a team decides to create power from the usage of solar, battery, or hydro power. An Electrical Engineer is highly valuable in this sense.
Having a scientist in your group could be a huge asset. Microbiologists, bioengineers, virologists, and immunologists could help to find a vaccine for the outbreak, and could be vital to helping diagnose certain diseases and providing certain amounts of medical care.
A botanist (biologist specializing in plants) could help to identify the different kinds of edible plants and help to grow plants once a base has been established. They may also be able to provide medical care through their knowledge of plants.
Chemists would be helpful in that they could make basic medicines, different kinds of explosives for the defense of the base, and could purify water and other foods
Now, more than ever, Children need to learn vital skills, and soon. Teachers can also act as babysitters. They also keep discipline among the children which is important since any noise they make will be heard by zombies or bandits.
This is a minor role, but important none the less. They can help keep the morale up. A comedy night, a play, even some juggling can help boost the morale of survivors. This should be considered a secondary job, but never underestimate the power of a heart-warming joke.
It will help shut up any actors or movie stars who demand they get the "respect" they deserve. It will also prevent people from going insane from boredom and hopelessness, and will go a long way in keeping people mentally healthy.
Par to farmers, fisherman can catch near-limitless food sources, but at a quicker rate. Skilled cooks will need the ability to prepare the fish that are caught for consumption.
This is a fairly minor role. It can be an unpopular job, but belief in a "higher" power can keep people sane and guide people through dark times. Be wary, as some may be radical and promote unsafe acts. Priests can act as a voice of reason in some debates and can be used to ease the guilt of a conflicted survivor after killing a hostile survivor or zombie.
These men and women are the backbone of their community, making and enforcing laws, as well as protecting the hard-working people that live and provide for each other. Without these, a new society would never reach success and the security that they so desperately cling to.
Lookout or Marksman
Lookouts take to the highest point in the settlement and keep an eye on the surrounding area. Lookouts will need a light source at night, binoculars, and an alarm which they can use to alert everyone else, in case danger arises. If armed, which is highly advised, lookouts become marksmen and are their settlement's first line of defense. They can take out lone or small groups of zombies or bandits that approach the base. Their weapons should be long range, and preferably with scope and suppressor attachments. It is advisable to assign working shifts to lookouts and marksmen.
Guard or Soldier
These guys should be strong so they can help keep the peace among the survivors. During non-conflict times, they will be the police force. If their settlement is attacked by bandits or zombies, they become foot soldiers. Make sure they know the law, enforce it and most of all, perform it effectively and fairly. Military combat arms personnel, combat veterans, and special response team personnel are excellent examples of individuals that can serve in this role.
These are more useful in the country than in the city, as they have a natural sense of the terrain. Hunting either zombies or whatever animals remain in the area, these can help keep the supplies coming in or threats such as feral animals under control. They can supply meats, furs, bones and help clear lone zombies from the area.
These need to be some of the toughest, most rugged people of their settlement, willing to kill for the benefit of their people. Although an unpopular decision, raiders will be needed if supplies are stolen, they are unable to create their own, or they are too lazy to obtain it themselves. Raiders should be trustworthy. Raiding will make them and their settlement feared and possibly attacked in reprisal, so they should only raid sparingly, if at all.