Biological wastewater treatment employs microscopic organisms to breakdown waste and ensure clean effluent. These “bugs” are often referred to as the hardest working employees at wastewater treatment facilities. As microscopes become a standard tool in wastewater facilities and laboratories, operators have an opportunity to add a powerful tool to their arsenal. This session will provide a background on the microbiology of activated sludge and explain how microscopic analysis can be used to dial in, troubleshoot, and maintain treatment facilities. Additionally, this session will also provide a brief overview of how to use microscopes, prepare samples, and analyze samples.