Water utilities increasingly operate at the intersection of competing priorities: expanding treatment capacity to accommodate growing sludge production, increasing renewable energy generation to support net-zero ambitions, and reducing greenhouse gas emissions. Anaerobic digestion (AD) is central to delivering these objectives, yet many full-scale digesters continue to operate conservatively using empirical stability thresholds and operational practices developed decades ago. This presentation synthesises over 15 years of research on intensification of sewage sludge ADs, aimed at helping the water industry unlock the untapped potential of existing assets. Drawing on full-scale, pilot-scale and laboratory studies delivered in collaboration with water utilities and waste companies, the presentation brings together findings from across scales and translates lessons between the water and waste sectors to explore the mechanisms that ultimately govern treatment capacity, energy recovery and process resilience. The work challenges traditional assumptions around digester stability and demonstrates that many of the current operational limits do not reflect the true capacity of modern digestion systems. While most ADs operate according to simple threshold values for volatile fatty acids, ammonia or organic loading rate defined according to feedstock type, performance is instead governed by the interaction between microbial community dynamics, process configuration and operational envelopes. The presentation will share insights from over a decade of innovation projects spanning advanced digestion retrofits, loading rate optimisation, inhibition management, targeted supplementation strategies and microbial adaptation, highlighting how innovation and mechanism-based operation can unlock treatment capacity while maintaining process stability and environmental performance.