Growing competition in the third sector has resulted in nonprofit organizations making more sophisticated use of marketing techniques to attract volunteers. Not only are organizations attempting to attract more volunteers but increasingly the focus is shifting to attracting the right type of volunteers, or those who will contribute the most hours. This study segments the volunteering market by number of hours contributed in the past 12 months, and identifies significant differences between the characteristics of high-contribution and low-contribution volunteers. High-contribution volunteers are found to (a) exhibit distinctive sociodemographic characteristics; (b) have a greater number, and broader range, of motivations for volunteering; and (c) initially get involved in volunteering in different ways to low-contribution volunteers. Findings are important because they provide practitioners with a description of those individuals most likely to contribute more hours, which can be used to increasingly attract these types of people and subsequently reduce the amount spent continually attracting new volunteers.