This document summarizes a presentation about probiotics in poultry nutrition. It discusses how single-strain probiotics often fail to reliably impact birds because they do not colonize the entire gastrointestinal tract or stay long after consumption stops. An effective probiotic should be multi-strain, species-specific, and well-positioned to colonize the whole GI tract, multiply faster, and be less eliminated. Trials demonstrate that the probiotic PoultryStar reduced issues like lameness, inflammation, and necrotic enteritis in poultry. The presentation provides information on selecting probiotic strains and applying probiotics in poultry to enhance immunity and gut health.