This April 2011 issue of The Police Chief contains seven primary articles that examine new tools and policies aimed at improving the safety and effectiveness of policing. Citizen Monitors, CCTV, and the Internet: A Combination to Consider examines the possibility of average citizens using CCTV feeds to their computers to assist law enforcement and report suspicious activities or crimes. Law Enforcement's Newest Weapon: Internet Scanning and Use of Social Media for In-Progress Crime, explores the use of social media and data mining as tools for tracking crime and criminals. Closed-Circuit Television: Peoria's Nuisance Property Surveillance Vehicles discusses Peoria, IL's use of an old security service armored truck to provide 24-hour camera surveillance of nuisance properties that destabilize and disrupt neighborhoods. Biometrics for Intelligence-Led Policing: The Coming Trends examines the use of biometrics to identify potential suspects. The Los Angeles Police Department's Hydra Program: Command Officer Training for Critical Incidents examines the Department's use of the Hydra Simulation System, an immersive simulation police training system developed in the United Kingdom for real-time decisionmaking during critical incidents. Safeguarding U.S. Nuclear Reactors and Nuclear Materials discusses the work of the U.S. Nuclear Regulatory Commission's Office of Investigations which conducts criminal and civil investigations related to the Nation's nuclear reactors and commercial uses of nuclear materials. Updating Ethics Training - Policing Privacy Series: Managing Risk by Reducing Internal Litigation discusses the need for law enforcement personnel to conduct themselves both on and off duty in accordance with their department's expectations, citizens' expectations, and ethical expectations. Also included in this issue is the 2011 Buyer's Guide for law enforcement officials. The guide includes a buyers' guide information, a listing of categories, a how to for using the guide, a directory of companies, and a list of products and services.