VACK is a non-governmental organization in Kenya that offers both short-term and long-term volunteer opportunities to support community development projects. Short-term projects last 1-3 weeks and focus on activities like teaching, caring for orphans, promoting sustainable agriculture, and organizing youth activities. Long-term projects last 1 month to 1 year in areas such as social work, education, art and culture, agriculture, and empowerment. The document provides details on specific volunteer projects for 2015, including locations and durations.