Background: Prior studies have shown that integration of early outpatient specialty palliative care (OSPC) with oncologic care improves patient’s symptom burden and quality of life. As a result, the American Society of Clinical Oncology (ASCO) recommends that OSPC be offered within 8 weeks of diagnosis of an advanced solid malignancy. Over the past decade, there has been an increase in the availability of OSPC services, particularly at National Cancer Institute (NCI)-designated cancer centers; however, the majority of OSPC referrals still occur late in the disease course. The aim of this study was to evaluate the facilitators and barriers to implementation of early OSPC. Methods: To assess the contextual determinants of early OSPC implementation, we developed a survey based on constructs from the Consolidated Framework for Implementation Research (CFIR), an implementation meta-framework. Using input from subject-matter experts, we tailored the survey to include a total of 18 relevant constructs from the 5 CFIR domains. The survey was distributed to the ambulatory palliative care (PC) clinical leader at NCI-designated cancer centers. The survey assessed each CFIR construct using a 5-point Likert Scale, where +2 represented the strongest facilitators, and -2 represented the strongest barriers. We inquired about respondent sociodemographics and OSPC clinic characteristics and used descriptive statistics to summarize responses to survey items. Results: Survey responses were collected between 12/15/21 and 1/18/22. Of the 63 NCI-designated cancer centers invited to participate, 40 (63%) completed the survey, while 3 (5%) did not due to not having an ambulatory program. All respondents were physicians. Half of the OSPC clinics were established for more than 10 years, and the majority (75%) provided care to more than 300 distinct outpatients annually. The most commonly agreed upon facilitators (Likert score = 1 or 2) to early OSPC included PC clinicians’ awareness of the ASCO recommendation for early OSPC (100%), informal communication between PC and oncology clinicians (100%), PC clinicians’ belief that OSPC improves the quality of oncology care (100%) and access to telemedicine (93%). The most commonly agreed upon barriers (Likert score = -1 or -2) included inadequate number of OSPC providers (73%) and lack of performance metric goals relating to early OSPC set by PC leadership (65%). Conclusions: Although OSPC clinics at NCI-designated cancer centers have grown over the last ten years, the utilization of early OSPC is impacted by the implementing institution’s resource availability, interdepartmental communication, stakeholder beliefs, and leadership engagement. Future studies should compare the barriers and facilitators of early OSPC identified by PC clinicians and oncologists to inform implementation strategies.