Natalie (Nat) was a child in an adult's body with her grandfather's implanted memories. Alone on an alien planet, she learned to survive and thrive. She fought slavery locally, then planet-wide, then across the Milky Way. When she learned to travel to other dimensions - associations between species became blurred and battles became horrific. Now - throw in near-immortality and extra-galactic threats and you have an interesting story. Carole, (from Uplift) is stranded in a remote area of the Milky Way and has to fight her way back to Earth. She learns to love travel and trade as she trains her disparate crew. Nat and Carole join forces to fight the slavers. Though MULTIPLE could stand alone - you would understand more if you have read Trade World Saga, Connection, or Uplift. If you've read them all - MULTIPLE ties them all together in the Trade World Universe.