This work proposes a national taxonomy through the identification and classification of dual career development environments in Spain. Based on the results of the Erasmus+ Ecology of Dual Careers project, a documentary analysis of the environments that promote dual careers at a national level has been carried out, as well as a verification and analysis of their characteristics and needs through work with dual career support providers. The results suggest the existence of three macrosystems: (a) public sports centres, (b) private sport clubs, and (c) educational centres. Public sport centres include high performance and sport technification centres. Private sports clubs include professional and amateur high-performance clubs, specialized and multi-sports. Finally, educational centres include institutes and universities. Each of these systems offers different dual career assistance programs. The figure of the support provider is repeated in a large part of the environments, as well as the fixed offer of services. The dual career assistance programs cover, for the most part, student-athletes who are in the same sport’s development stages (i.e., junior) and academic/professional levels (i.e., secondary education). As elements for improvement, there is a lack of environments that promote the combination of sports and work, as well as extending this exercise to student-athletes who represent vulnerable populations (e.g., athletes with disabilities).