The Moat Around Murcheson's Eye

Amazon editorial review This is the sequel to "The Mote in God's Eye". Humankind has spent 100 years agonizing over the threat posed by the only aliens they have ever threatened, the Moties. The three-armed aliens have been quarantined within the confines of their own solar system - until now.

also by Larry Niven in our collection:

• Lucifer's Hammer
• Inferno
• Man-Kzin Wars
• A Gift from Earth
• A Hole in Space
• The Long Arm of Gil Hamilton
• The Mote in God's Eye
• Neutron Star
• The Patchwork Girl
• Protector
• Ringworld
• The Ringworld Engineers (Orbit Books)
• Ringworld Throne
• Tales of Known Space
• The World of Ptavvs (Tales of Known Space)