Diseases caused by oomycete plant pathogens result in devastating losses to agriculture and native forests, despite the significant research efforts that have advanced our understanding of these organisms. Limiting these pathogens has been challenging to plant pathologists and plant health practitioners. In this first focus issue , titled Managing Stubborn Oomycete Plant Pathogens, Plant Health Progress has assembled an array of manuscripts on the biology and management of Phytophthora, Pythium, Pseudoperonospora, Peronospora, and Aphanomyces spp. This focus issue has 28 peer-reviewed papers including three diagnostic guides, three mini-reviews, three briefs, two surveys, and 17 research papers. Of the 28 papers, 20 are on diseases caused by Phytophthora, four on Pythium, three on downy mildews, and one on Aphanomyces. All advance our understanding of these stubborn oomycete pathogens.