INFORMATION ON WHAT FEATURES TO LOOK FOR IN CHOOSING A LOCK IS PRESENTED; THE LOCK-IN-KNOB LOCKSET IS TO BE AVOIDED. TWO BASIC TYPES OF LOCK BOLTS USED IN DOOR LOCKS, LATCH BOLTS AND DEADBOLTS, ARE DESCRIBED IN TERMS OF MECHANISM. SUGGESTIONS ARE PROVIDED ON HOW TO INSTALL LOCKS SECURELY. ALSO DISCUSSED ARE CYLINDER GUARDS (TO PREVENT THE BURGLAR FROM OPENING LOCKS THROUGH CYLINDER PULLING OR WRENCHING) AND STRIKES. A DISCUSSION ON PADLOCKS INCLUDES TUMBLER MECHANISMS, POSITIVE LOCKING, HEEL AND TOE LOCKING, THE IMPORTANCE OF TOUGH CASES AND CASE-HARDENED AND SHIELDED SHACKLES, AND HASPS. OTHER TYPES OF LOCKS ARE BRIEFLY MENTIONED.