The trans-contextual model outlines the motivational processes by which forms of motivation towards activities in a physical education context translate to motivation toward, and actual participation in, physical activities in a related non-educational context. While the model has been used in multiple health domains and across different populations, recent evidence syntheses have identified key limitations including the prevalence of correlational designs limiting causal inferences, a focus on reasoned motivational processes, and excess use of self-report behavioural measures. This chapter provides an updated overview of conceptual and empirical advances, with particular emphasis on evaluating the extent to which these advances have addressed previously identified issues and gaps in the evidence. We highlight recent research that has extended the model by including additional constructs like basic psychological need satisfaction, mindfulness, and perceived autonomy support from other social agents, broadening its predictive scope. We discuss the adoption of alternative research designs like experiments/interventions and longitudinal cross-lagged panel designs to better infer causality, directionality, and reciprocity in model effects, and the use of non-self-report behavioural measures like accelerometers. Furthermore, we discuss the practical relevance of the model in informing interventions to foster motivation across contexts, while acknowledging the need for further research testing the efficacy of the model.