Abstract Purpose In reports of end‐of‐life communication interventions, it is difficult to find sufficient detail about the intervention to allow replication, extension, and translation into practice. The purpose of this article is to provide details about a theory‐guided advance care planning intervention, sharing the patient's illness representations to increase trust (SPIRIT), an intervention that has been shown to be efficacious for patients and their surrogates with respect to preparation for end‐of‐life decision making. Methods and Design The description of SPIRIT is based on an intervention description checklist by Conn (2012), the Intervention Taxonomy from Schulz, Czaja, McKay, Ory, and Belle (2010) and on relevant segments of Consolidated Standards of Reporting Trials. Discussion The SPIRIT intervention was developed based on sound theoretical underpinnings and pilot tested with target patient populations and racial or ethnic groups. We describe details about the intervention's theoretical basis, requisite intervener training, implementation of each intervention component, and fidelity monitoring. Clinical Relevance The details about the components of a theory‐guided advance care planning intervention may facilitate translation of the intervention to practice settings.