Abstract: This research was focused on developing a new scientific approach for prioritising recycling of end-of-life products in a circular economy. To date, product complexity based on the mixture of materials has been used as a predictor of what gets recycled. While the separation of materials that make up a product has been modelled as a measure of product complexity, this does not taken into account the benefits and considerations in recycling products. In this paper, a new agenda and approach to prioritise the recycling of products was developed based on a recycling desirability index. The material mixing complexity measure was inverted into a simplicity index and then extended by modelling the security index for the mix of materials and the technological readiness level of recycling technologies. The extended model is proposed as an integrated measure of the desirability of recycling end-of-life products. From this analysis, an apparent recycling desirability boundary, enabling products to be prioritised for recycling, was developed. This model and analysis can be used as an information source in developing policies and product recycling priorities.