Wastewater treatment processes that recover acceptable amounts of nutrients with minimal environmental impact are a key challenge. Environmental impact of nutrient recovery technologies can be estimated by life cycle assessment (LCA), which allows us to compare potential environmental impacts of fertilizers obtained from recovered nutrients to that of conventional fertilizers. LCA environmental modelling helps to develop sustainable wastewater treatment systems with integrated nutrient recovery (struvite and biosolids), water purification for irrigation, energy production (biogas), and useful chemicals production. In order to determine the most efficient, cost-effective technologies for nutrient recovery we also need to consider how nutrients can be recovered from wastewater sources. Wastewater treatment provides existing systems and technologies which may be adaptable for nutrient recovery rather than just nutrient removal. Development of newer, more energy-efficient, cost-effective, modular, transportable, or multiple-use integrated systems will provide more adaptable systems to improve the recovery of nutrients and other products, according to local needs. Emerging technologies such as ionexchange electrolysis and reverse osmosis have already proved themselves useful for recovering nutrients from wastewater. Innovative technologies for developing sustainable fertilizers and nutrient delivery systems include the recovery of valuable nutrients from wastewater producing struvite and other fertilizer alternatives. Recycling and recovery of phosphorus fertilizers has been commercialized. Integrated commercial processes of phosphorus recovery as struvite are commonly employed at wastewater treatment plants. The AirPrex process is a robust technology for struvite production. In the AirPrex reactor, wastewater sludge is subjected to CO2 stripping through aeration followed by addition of Mg salts that leads to the formation of struvite. Ostara's PEARL process is widely used for phosphorus recovery from municipal and industrial wastewater through the controlled precipitation of crystalline struvite. Thermochemical phosphorus recovery from wastewater (the AshDec process) occurs through wastewater sludge anaerobic stabilization followed by sludge incineration and production of phosphate-rich ashes. The ashes obtained by the AshDec method are free from Pb, As, Cd and other heavy metal compounds since they are evaporated during incineration. The RecoPhos process is another thermochemical process that provides a novel approach for the recovery of so-called white phosphorus (or phosphoric acid as its oxidized form) from sewage sludge ashes. The innovative reactor used in the RecoPhos method allows the reduction of ash phosphates in the thin film on the surface of coke particles. The reduced P is evaporated from the film without reacting with other elements.