According to water and wastewater industry experts, less than half of all automated process control systems really work. Studies in the private sector indicate that 50-75% of advanced technology implementations fail. About 400 water and wastewater managers of working computer control systems were surveyed to determine their perspectives on critical variables affecting control system success. Responders said human and organizational, rather than technical, factors are most critical. This paper, coauthored by a senior control systems engineer and a human factors management consultant, summarizes their insights and presents practical advice for anyone who wants to make control systems successful.