Current-use and legacy pesticides have been detected throughout the San Francisco Bay in surface water and sediment. However, it is difficult and expensive to use traditional sampling techniques in the estuary due to complex hydrodynamics and episodic pulses of pesticides. Passive samplers are important tools used to monitor bioavailable pesticides by collecting an integrative sample over time resulting in fewer samples and eliminating the need to catch definitive "pulses" of pesticides. Measuring various classes of pesticides can be difficult due to the range in their hydrophobicities (log K_ow < 2 to >6). SPMDs (log K_ow > 4) and POCIS (log K_ow < 4) were deployed in tandem at several marsh sites in upper San Francisco Bay to monitor pesticides. Surface water samples were also collected to compare pesticides detected in a typical 1-L point sample to those detected in passive samplers deployed for a month. The more hydrophilic current-use pesticides fipronil, metolachlor, pendimethalin, simazine and trifluralin, were detected in both the POCIS samplers and the 1-L water sample collected at time of deployment and retrieval. The more hydrophobic legacy organochlorine insecticides were detected only in the SPMDs and included DDTs, dieldrin and several chlordanes. Concentrations of these pesticides measured in the SPMDs were below the detection limit for the 1-L water sample. Pyrethroids are a class of current-use pesticides that are increasing in use and are of concern due to their high aquatic toxicity. Pyrethroids are relatively hydrophobic (log K_ow = 4-6) and should be sampled by SPMDs. However, preliminary results suggest that the size and steric hindrance of the pyrethroids may limit their ability to pass through the SPMD membrane. Future work will include laboratory uptake studies to validate the effectiveness of SPMDs and POCIS for measuring current-use pesticides, including pyrethroids, in surface waters.