With warm weather approaching, many seniors consider giving of themselves. Lifetimes of business, teaching, travel and other skills make seasoned citizens very valuable to their communities and beyond. Here are just a few major volunteer programs to ponder:

USO: Since World War II, the USO has provided services to members of the Armed Forces and families. Seniors may participate in ongoing activities, as well as for special events. USO volunteers are at many major airports, train stations and bus depots, offering snacks and comfortable waiting areas for traveling military.

Senior Corps: Among other services, the volunteer program includes foster grandparents, senior companions and RSVP (Retired Seniors Volunteer Programs). One volunteer service is driving physically-challenged seniors to medical appointments and for grocery shopping.

Meals on Wheels: There are 5,000 branches of the program in the U.S. Volunteers deliver nutritious food to seniors in community centers and private homes. For those who can't pay, meals are free. For others, the charge is just a few dollars.

ASPCA: Senior volunteers help with runaway dogs, abandoned pets and animal medical problems. They may also aid in grooming and preparing pets for adoption.

United Way: The nationwide agency promotes its annual National Volunteer Week in mid-April, and Day of Action in early June. Hundreds of affiliated organizations reach out to recruit volunteers of all ages.