In past centuries in the United States (and still in many parts of the world today), extended families lived together in the same town, in the same neighborhood, or under the same roof. Elders looked after grandchildren, and siblings worked with parents. One's extended family was nearby to offer moral and financial support in the bad times and celebrate milestones, birthdays, and other occasions in the good.

Today that isn't always the case. College, jobs, or marriage can take people across the country — or the world — and far away from their families, old friends, and the places where they grew up. Unless you're adept at forging deep friendships quickly, you may not develop the social support network of family, friends, and coworkers in your new place that you had in the old. Sometimes such a lack of community can lead to loneliness. Research has shown that social isolation has real detrimental health effects, such as high blood pressure, disrupted sleep, and depression. Indeed, some researchers surmise that loneliness can be as bad for your health as a poor diet or lack of exercise.

Life-changing circumstances, such as having a child, becoming seriously ill, or natural or other disasters, such as hurricanes or 9/11, can change your perspective on where you want to live. You may want to move closer to family or friends to enjoy the benefits of a close-knit social and emotional support system. Most people want to feel safe and secure in their surroundings. In 2006, North Dakota was ranked the country's Safest State for the ninth time by the Morgan Quitno Press. Other states on the “safe” list include Maine, Vermont, New Hampshire, and Wyoming. Out of 369 cities considered, the country's safest include Newton, Massachusetts; Clarkstown, New York; and Mission Viejo, California. The rankings are based on FBI data for murder, burglary, motor vehicle theft, and other factors.

Support can include other things besides family, too. Some people prefer to be near those who share their heritage or speak their native language, even if they aren't related. Many people whose religious beliefs form an integral part of who they are want to reside in a community that shares their faith. Other forms of support include excellent health care facilities, educational opportunities if you decide to advance or change careers, affordable child care, and good public transportation systems.

Depending on your circumstances, any combination of these factors can dramatically affect your choice of location.