Optimal physical performance is a product of specific and tailored training. There are well-established sex differences in anatomical, physiological, and performance factors between biological males and females, which may have implications for physical preparation. A potential knowledge gap exists in relation to sex-specific differences in physical preparation because practitioners largely rely upon empirical evidence collected in male subjects for reference when devising interventions for female athletes. Therefore, this study explored the attitudes, beliefs and practices of strength and conditioning coaches (n = 8; M/F, 6/2) in elite level (international) women's rugby union using semi-structured interviews (mean ± standard deviation duration 59 ± 15 minutes). The interviews explored differences in coaching elite female rugby players compared to males, with specific focus on training methodologies and understanding of pertinent aspects of female physiology. Reflexive thematic analysis was utilised to generate a rich qualitative dataset. Analysis resulted in the identification of higher-order themes: developmental stage of women's rugby, physical preparation, and education. Additional subthemes were created to facilitate organisation and presentation of data. The majority of coaches consider sex-specificity when devising physical preparation interventions as a function of training experience, rather than physiological between-sex differences, yet there were conflicting, and often erroneous understanding of female-specific considerations. To the authors knowledge, this is the first study to investigate attitudes, beliefs, and practices in elite level strength and conditioning coaches regarding sex-specific differences, and as such, illustrates the current understanding and opinions of practitioners in international level women's rugby union.