Phenology provides vital insights into species reactions to climate change; alterations in species phenologies can result in disturbances to the ecological processes and services that humans rely on. Long-term phenological records covering multiple taxa and a wide geographic distribution are required for scientists to better detect such alterations. To date, phenological observation efforts in the United States have been geographically limited and have used disparate approaches, making comparisons between sites and species challenging. The USA National Phenology Network has developed in situ monitoring protocols standardized across taxonomic groups and ecosystem types for terrestrial, freshwater, and marine plant and animal taxa to facilitate coordinated cross-site, cross-species, and geographically extensive phenological monitoring across the country. The protocols include elements that allow enhanced detection and description of phenological responses, including assessment of phenological “status”, or the ability to track presence–absence of a particular phenophase, as well as standards for documenting the degree to which phenological activity is expressed in terms of intensity or abundance. Data collected by this method can be integrated with historical phenology data sets, enabling the development of databases for spatial and temporal assessment of changes in status and trends of disparate organisms. and temporally extensive multi-taxa phenological data set available for a variety of research and science applications, we encourage scientists, resources managers, and others conducting ecological monitoring or research to consider utilization of these standardized protocols for tracking the seasonal activity of plants and animals.