J.W. Mitchell, N.B. Mandava and others' 1970 publication in Nature, "Brassins-A New Family of Plant Hormones from Rape Pollen" announced the discovery of a new plant hormone, brassinolide, which would also mark the sixth and newest group of plant hormones, brassinosteroids. This monograph details the early research leading to the isolation and synthesis of the first brassinosteroid to current research in the field. The 50 years of brassinosteroid research can be separated in two parts; The first 25 years saw the innovation of different bioassays and isolation techniques while the last 25 years saw the investigation into brassinosteroids signaling, cross talk, stress response, and agricultural application. Since the discovery of brassinolide, there have now been 62 brassinosteroids identified through international research efforts. Several of these have been targeted for agricultural use with patents in many countries. Homobrassinolide is one such brassinosteroid that helps improve crop yield and fruit sweetness while conferring stress resistance. This monograph is the first to fully encompass the story of brassinosteroids.Progress in the First 25 YearsDiscovery of Brassins 1970 - Mitchell, Mandava, and others (Nature article)Screening of Various Kinds of PollenBrassins - Field trials in Brazil and the USADiscovery of BrassinolideDetection of active ingredient by Bean Second-Internode BioassayIsolation from Rapeseed (Brassica napus L.) PollenDevelopment of Laboratory Scale Purification MethodPilot-Plant Extraction of PollenIdentification of BrassinolideSynthesis of Brassinolide Structure-Activity of Brassinolide AnalogsSynthesis of Brassinolide from sterol isolated from oystersOther Synthetic Methods for BrassinolideDevelopment of Other Bioassays -Screening of Brassinosteroids using Various BioassaysDevelopment of Sensitive Analytical Methods for Detection of BrassinosteroidsIsolation of Other Brassinosteroids from Various Plant Sources Synthesis of Other BrassinosteroidsSelection of three Brassinosteroids based on BioassaysMetabolism of BrassinosteroidsBiosynthesis of BrassinosteroidsProgress in the Second 25 YearsBrassinosteroid SignalingBrassinosteroid CrosstalkPhysiological ResponsesSenescenceStress ResponsesPathogen AttackGene RegulationSignal TransductionMetabolism of Brassinosteroids (cont.)Brassinosteroid Bio efficacyAgricultural UsesMode of Action and Economic BenefitsField Trials