Background The uptake of guidelines in care is inconsistent. This review focuses on guideline implementation strategies used by guideline organizations (governmental agencies, scientific/professional societies and other umbrella organizations), experienced implementation barriers and facilitators and impact of their implementation efforts. Methods We searched PUBMED, EMBASE and CINAHL and conducted snowballing. Eligibility criteria included guidelines focused on hospital care and OECD countries. Study quality was assessed using the Mixed Methods Appraisal Tool. We used framework analysis, narrative synthesis and summary statistics. Results Twenty-six articles were included. Sixty-two implementation strategies were reported, used in different combinations and ranged between 1 and 16 strategies per initiative. Most frequently reported strategies were educational session(s) and implementation supporting materials. The most commonly reported barrier and facilitator were respectively insufficient healthcare professionals’ time and resources; and guideline's credibility, evidence base and relevance. Eighty-five percent of initiatives that measured impact achieved improvements in adoption, knowledge, behavior and/or clinical outcomes. No clear optimal approach for improving guideline uptake and impact was found. However, we found indications that employing multiple active implementation strategies and involving external organizations and hospital staff were associated with improvements. Conclusion Guideline organizations employ diverse implementation strategies and encounter multiple barriers and facilitators. Our study uncovered potential effective implementation practices. However, further research is needed on effective tailoring of implementation approaches to increase uptake and impact of guidelines.