Learning management systems (LMSes) are the technology that manages corporate eLearning around the globe. Forrester estimates that the LMS market currently exceeds $3 billion. This market is changing rapidly, with some companies on their second or third LMS implementation as they search for a more personalized, easy-to-use application that fits the lifestyles of today's employees. This report examines the features and differentiators of the products of 21 standalone LMS vendors to help application development and delivery (AD&D) professionals understand the market and its players.