Bovine respiratory disease complex (BRDC) is one of the most important multifactorial disease syndromes affecting cattle and is associated with substantial economic losses through morbidity, mortality, treatment costs, and reduced production efficiency. BRDC develops through complex interactions among environmental and management stressors, host factors, primary viral infections, and secondary bacterial pathogens. This review summarizes current knowledge of BRDC pathogenesis, diagnostic approaches, and therapeutic and preventive strategies. Important viral agents include bovine respiratory syncytial virus, bovine parainfluenza virus type 3, bovine herpesvirus-1, and bovine viral diarrhea virus, while major bacterial pathogens include Mannheimia haemolytica, Pasteurella multocida, Histophilus somni, and Mycoplasma bovis. Viral infection and stress can impair respiratory defenses and facilitate bacterial colonization of the lower respiratory tract. Diagnosis remains challenging because clinical signs are often nonspecific and molecular detection may identify organisms that are present without being the primary cause of disease. Multiplex quantitative PCR has expanded the capacity for simultaneous pathogen detection, but results must be interpreted together with clinical, pathological, and epidemiological findings. Effective control requires integrated herd management, including stress reduction, biosecurity, strategic vaccination, early diagnosis, and prudent antimicrobial use. Future advances will depend on improved vaccines, better host-response biomarkers, refined diagnostics, and sustainable alternatives to conventional antimicrobial therapy.