Although biologic therapies have greatly improved outcomes among patients with inflammatory diseases, a proportion of patients will develop an immunogenic response, which may result in reduced efficacy, loss of response and/or adverse events. However on an individual basis these relationships are highly variable. Although standard IBD treatment currently incorporates screening and monitoring for immunogenicity, eg therapeutic drug monitoring (TDM), this has not been broadly utilized in rheumatology practice. Rheumatologists are able to rely on routine clinical monitoring and many non-responsive patients show no evidence of immunogenicity. Further there are significant barriers to the effective use of commercially-available assays. As all biologic agents are associated with various immunogenicity profiles, a comprehensive understanding of the role that immunogenicity plays in the use of biologic therapies will benefit rheumatologists and other healthcare providers.