The Albuginales (Oomycetes) consist of obligate biotrophic pathogens, none of which is culturable on artificial media. This group causes white blister rust disease in diverse angiosperm plants, including many economically important crops such as sunflower, horseradish, rape, radish, spinach, and wasabi. Recent advances in molecular phylogenetic tools and findings of new morphological characters have advanced our knowledge on their diversity, evolution, and systematics. This review introduces the white blister rusts and discusses recent innovations resulting from studies on Albuginales.