Moss Landing Marine Laboratories (MLML) Marine Pollution Studies Lab (MPSL) was established in 1977 by a handful of ambitious students, led by Mark Stephenson. This small group of future California Department of Fish and Wildlife (DFW) staff established the California Mussel Watch Program which transplanted mussels up and down the California coast as biosentinels to identify organic contaminant and tributyl tin hotspots. In 1992, under the lead of Rusty Fairey, MPSL expanded it’s scope and took the reins of California’s Bay Protection and Toxic Cleanup Program (BPTCP) which provided the first comprehensive statewide sediment survey of contaminants in California’s bays and harbors. By the late 1990’s toxic hot spots had been identified throughout the state and sediment cleanup and restorations actions were implemented. The successes of the BPTCP provided the legislative momentum for the initiation of the Surface Water Ambient Monitoring Program (SWAMP) an ambitious ongoing California statewide program that focuses on water quality and biological health in California’s lakes, rivers and streams. In the 2000s MPSL started the first large scale mercury project in the San Francisco Bay-Delta which included fish monitoring as well as developing a mass balance for the entire system. In 2010s MPSL continued work upstream of the Delta in the Sacramento Valley’s Yolo Bypass with a focus on mercury and rice agriculture and ways to manage agricultural and non agricultural lands to minimize production and export of organic mercury. MPSL was also a part of a group that identified marine advective fog as a new transport pathway for organic mercury. Currently MPSL is collaborating with California Department of Water Resources to develop a working mercury model of the San Francisco Bay Delta. In 2012, Wes Heim assumed the lead role at MPSL-DFW as Mark Stephenson retired from day to day operations. Mark’s trailblazing spirit and legacy of applied research is still much appreciated and his occasional presence around the lab is always welcome. These are just some of the many highlights over the years which MPSL can proudly point to as an outgrowth of skills and dedication that were nurtured in the early years at MLML and that have matured into a world class marine pollution research facility.