Environmental DNA (eDNA) sampling - which enables inferences of species’ presence from genetic material in the environment - is a powerful tool for sampling rare fishes. Numerous studies have demonstrated that eDNA sampling generally provides greater probabilities of detection than traditional techniques (e.g., Thomsen et al. 2012; McKelvey et al. 2016; Valentini et al. 2016; Wilcox et al. 2016). In contrast, Ulibarri et al. (2017) and Perez et al. (2017) reported unusually low rates of eDNA detection at sites known to be occupied by the target species. These authors claim their results demonstrate that traditional sampling methods, based on best practices developed by experienced biologists (Bonar et al. 2009), are more accurate and sensitive for rare species detection than eDNA sampling. We believe the authors would have achieved substantially higher species detection rates and provided more useful comparisons with traditional sampling methods if they had adopted best practices for eDNA sampling (e.g., Goldberg et al. 2016). Here we focus on three elements of eDNA sampling and analysis that are critical to maximizing species detection rates: (1) the volume of water sampled in the field, (2) the volume of each sample that is analyzed in the laboratory, and (3) assessment of potential chemical inhibitors of laboratory eDNA detection.