Advantage Publishers Group (APG) publishes books under three imprints: Silver Dolphin Books, Thunder Bay Press, and Portable Press. Founded over fifteen years ago, Advantage Publishers Group has a growing list of published titles and now has a backlist of more than 500 books. APG books are sold in the United States and throughout the world.

Thunder Bay Press, APG's first imprint, published its first title in 1990. Silver Dolphin Books quickly followed. Finally, in 2000, APG purchased the best-selling Uncle John's Bathroom Reader series and created Portable Press as an imprint to house this list. Advantage Publishers Group is the umbrella organization under which all three imprints operate.