Objectives: Since abortion laws were liberalized in Western Europe, conscientious objection (CO) to abortion has become increasingly contentious. The objectives of this study were to assess the efficacy and acceptability of national policies that attempt to enable both CO and access to legal abortion services. Do their regulations effectively permit CO while still ensuring that women have access to abortion care? Methods: This was an exploratory multiple-case study of England, Italy, Norway and Portugal’s approaches to regulating conscientious objection to legally permissible abortion. Multiple data sources were collected and triangulated, including legal and regulatory documents, historical analyses, contemporary health system assessments, and interviews with key stakeholders from all sides of the debate. Results: While the laws in all four countries have similarities, we found that implementation varied. In this sample, the ingredients that appear necessary for a functional health system that ensures access to abortion while still permitting CO include: clarity about who can object and to which components of care; ready access by mandating referral and/or establishing direct entry; and assurance of a functioning abortion service through direct provision or by contracting services. Social attitudes towards both objection and abortion additionally influence the degree to which CO policies are effectively implemented in these cases. Conclusion: England, Norway and Portugal illustrate that it is possible to accommodate individuals who object to providing abortion, while still assuring that women have access to legal healthcare services.