The job demands-resources (JD-R) model provides a well-validated account of how job resources and job demands influence work engagement, burnout, and their constituent dimensions. The present study aimed to extend previous research by including challenge demands not widely examined in the context of the JD-R. Furthermore, and extending self-determination theory, the research also aimed to investigate the potential mediating effects that employees’ need satisfaction as regards their need for autonomy, need for belongingness, need for competence, and need for achievement, as components of a higher order needs construct, may have on the relationships between job demands and engagement. Structural equations modeling across two independent samples generally supported the proposed relationships. Further research opportunities, practical implications, and study limitations are discussed.