The Thesis demonstrates the potential of enhanced phosphorus removal from municipal wastewater using microalgal biomass exposed to phosphorus deficiency conditions. The study focuses on identification of appropriate microalgal species for production in municipal wastewater after P-starvation, developing a reliable P-starvation technique and identifying indicators for phosphorus deficiency status quantification. Further, the optimum initial conditions for rapid phosphorus removal and valuable algal biomass production have been identified and verified during a continuous process in a sequencing batch photobioreactor. The author of this study shows that the results from batch experiments and optimization model validation in sequencing batch photobioreactor have provided knowledge that can be used for existing industrial scale microalgae cultivation systems as well as for microalgal based wastewater treatment system development.