PCAS

PCAS may refer to:


 * Palomar Planet-Crossing Asteroid Survey, astronomical survey
 * Patient-controlled analgesia methods
 * Persistent Close Air Support
 * Personal Carbon Allowances, a concept in Personal carbon trading
 * Polytechnics Central Admissions System
 * Portable Collision Avoidance System
 * Postgraduate Certificate in Antarctic Studies at University of Canterbury
 * Post-Cardiac Arrest Syndrome