In today's fast-changing urban labor markets, skill formation is crucial to long-term income security and occupational advancement. While most studies emphasize the skills that workers acquire through formal training and educational programs, a less understood but equally important concern is how workers acquire skills through informal means and then how they demonstrate and defend skills for which they have no formal credentials. This is especially important when considering the labor market participation of less-educated immigrant workers with limited formal training and credentialing support. How do these immigrant workers develop, demonstrate, and defend their skills in receiving community labor markets? What factors facilitate or hinder these processes? How might skill formation be institutionalized in order to enhance immigrant labor market incorporation? In this paper we examine these questions through a study of Latino immigrant workers in North Carolina's construction industry. In particular, we focus on the role that immigrant skills intermediation, and the informal learning processes it supports, play in the formation of emergent pathways for developing, demonstrating, and defending immigrant talent in mainstream labor markets. We conclude that informal intermediation by established immigrant workers can facilitate immigrant skill development and demonstration in mainstream labor markets and thus provides an important pathway for advancing the labor market status of less-educated immigrant workers.