Clear communication between primary care physicians and the providers to whom they refer patients has important implications for achieving accurate diagnosis and appropriate treatment plans for patients. In this observational study, researchers included 6603 patients from 68 general medical practices in Ireland, randomly selecting 100 patients from each practice and excluding patients without complete records. They analyzed referral documentation and responses received from subspecialists as well as discharge summaries from hospitalizations over a 2-year period, compared with established national standards. Although 82% of referral letters included current medications, only 30% of response letters and discharge summaries contained medication changes and 33% had medication lists. The authors conclude that significant communication gaps exist between primary and secondary care and that further research is needed to understand how to address them. A past PSNet perspective discussed challenges associated with care transitions.