This review aims to discuss the current state of surgical antimicrobial prophylaxis (SAP) evidence for surgical site infection prevention. Despite decades of research, knowledge gaps persist in identifying optimal SAP regimens. Recent randomised controlled trials highlight ongoing heterogeneity in study design. Key new findings support the use of oral preoperative SAP for colorectal surgery and advise against the use of SAP for transperineal prostate biopsy. There is growing evidence for culture-based SAP over empiric use for transrectal prostate biopsy.Contentious issues remain regarding topical antimicrobials for cardiac procedures involving sternotomy, the necessity of SAP for wire lumpectomy and laparoscopic cholecystectomy for both mild or moderate acute cholecystitis. Procedures where SAP is not indicated, yet research is still being conducted on this topic include dental implants and clean orthopaedic procedures. Research efforts continue with numerous trials published and registered to determine optimal SAP regimens. However, many efforts are suboptimal due to poor statistical design and redundant questions already answered by existing literature. To improve practice and influence surgeons prescribing behaviour future RCTs should be well powered, with large sample sizes across multiple sites, focusing on clinically relevant questions.