BACKGROUND: The findings from multi-centre trials are central to the practice of evidence-based medicine, enabling the development and implementation of new treatments. The time it takes to commence clinical trials at sites can be long, and ethics and governance approvals are key steps on the pathway to site activation. The goal of this study was to explore factors influencing the times to ethics approval, governance approval and site activation for multi-centre clinical trials. METHODS: This paper assessed the associations of trial characteristics (disease area and trial phase), site characteristics (government or private ownership, country) and characteristics of the ethics and governance processes (scope guidelines, mutual acceptance requirements and triage of projects by risk) with times to approvals and activation. Median times were compared between site initiations that were and were not exposed to each characteristic using non-parametric tests in univariable and multivariable regressions. RESULTS: There were data from 150 site activations done across 91 sites, 16 trials and 5 countries from November 2013 to November 2021. The overall median time to activation was 234 days (range 74 to 657), with ethics approval taking a median of 48 days (0 to 369) and governance approval a median of 34 days (0 to 489). Both the univariable and multivariable analyses identified associations of disease area, particularly oncology (p univariable = 0.012, p multivariable = 0.044), use of scope guidelines (p < 0.001, p = 0.020) and use of a triage process (p < 0.001, 0.043) with shorter median times for governance approval. These characteristics (all p < 0.001) plus early trial phase (p = 0.028) were also predictive of shorter median times for ethics approval in univariable analyses, but none remained predictive in multivariable models (all p > 0.054). The only factors associated with reduced overall time to site activation in both univariable and multivariable analyses were the early trial phase (p < 0.001, p = 0.013) and mutual acceptance of ethics approvals (p = 0.031, p = 0.030). INTERPRETATION: Times to ethics and governance approvals were only one third of total trial start-up time. Factors influencing times to approval and activation were somewhat inconsistent across analyses, but it seems likely that the introduction of selected governance and ethics processes can reduce approval times.