Health care spending exceeds national gross domestic product growth and continues to jeopardize the U.S. economy. Health care Group Purchasing Organizations (GPOs) may encounter challenges in achieving member commitment because no formal authority exists between GPOs and their members. Therefore, mandatory commitment from GPO members is not required, purchasing decisions remain outside the GPO’s span of control, and declination of advice, recommendations, or requests may occur without legitimate reasons. The general business problem is that GPO members may not achieve the lowest available prices on medical supplies and therefore contribute to excessive health care spending. The specific business problem is that GPOs may not use the appropriate influence strategy to persuade their members to remain committed to desirable purchasing behavior. This book reveals the relationship between GPO employees’ characteristics and the use of influence strategies. The conceptual framework is derived from Kipnis’s, Schmidt’s, and Wilkinson’s strategic influence concept. The quantitative analysis should be especially useful to professionals in Sales, Marketing, and Consulting fields.