"Fleet of Worlds" marks Larry Niven's first full novel-length collaboration within his Known Space universe, the playground he created for his bestselling Ringworld series. Teaming up with fellow SF writer Edward M. Lerner, "Fleet of Worlds" takes a closer look at the Human-Puppeteer (Citizens) relations and the events leading up to Niven's first Ringworld novel.

Kirsten Quinn-Kovacs is among the best and brightest of her people. She gratefully serves the gentle race that rescued her ancestors from a dying starship, gave them a world, and nurtures them still. If only the Citizens knew...

For decades, the spacefaring species of Known Space have battled over the largest artifact--and grandest prize--in the galaxy: the all-but-limitless resources and technology of the Ringworld. But without warning the Ringworld has vanished, leaving behind three rival war fleets.

Something must justify the blood and treasure that have been spent. If the fallen civilization of the Ringworld can no longer be despoiled of its secrets, the Puppeteers will be forced to surrender theirs. Everyone knows that the Puppeteers are cowards.

But the crises converging upon the...