Community-academic partnerships are believed to increase the effectiveness and feasibility of action research. While factors facilitating and hindering community-academic partnerships have been identified, their influence on the collaborative process is unknown, especially during community-academic partnership initiation and development. This explanatory sequential mixed methods study (quantitative[right arrow]QUALITATIVE) evaluated perspectives of members in an autism community-academic partnership to determine frequently endorsed and influential factors facilitating and hindering the collaborative process during the community-academic partnership's development. Participants (n = 11; community stakeholders, implementation scientist, and researchers) endorsed and ranked the importance of factors present in the formation of the community-academic partnership then completed a semi-structured qualitative interview to elaborate on survey responses. Interviews were coded using a coding, comparison, and consensus method and analyzed using the Rapid Assessment Process for frequency and salience of themes across interviews. Integrating mixed methods yielded ranked factors that were perceived to facilitate and hinder the development of the community-academic partnership, and highlighted the relative influence of interpersonal factors on the facilitation of community-academic partnership processes and organizational factors on the hindrance of community-academic partnership processes during development. Some discrepancies emerged between community and academic partners. Results may assist to improve the development of community-academic partnerships, which is becoming increasingly important in healthcare services research, dissemination, and implementation. [This paper was published in "Action Research" v19 n2 p277-300 Jun 2021.]