The paper presents the outcome of a comprehensive study analysing results from a computational fluid dynamics (CFD) simulation, including detailed chemical kinetics and experimental work applied to reburn technology to reduce NOx emissions in pulverised coal fired boilers. These different approaches to optimise the reduction of NOx emission have advantages and disadvantages when applied to the design of reburn installations for retrofit or new boilers. The integrated use of the three approaches represents a powerful tool for reburn technology implementation. The objectives of the present paper are to show the importance of these three different approaches when they are used together; to analyse results, in order to better understand the reburn technology; and to provide some indications for implementation of reburn technology. The influence of stoichiometric ratio, temperature and NOx concentration was studied and results from CFD modelling are presented. These show that NOx reduction efficiency is strongly dependent on the local conditions inside the reburn zone, as well as the average values. This shows the importance of having CFD models coupled with detailed chemical kinetic schemes. The efficiency of NOx reduction using coal as reburn fuel instead of natural gas was also analysed. The study of the influence of NH3 injection above reburn injection (advanced reburn technology) is presented in the paper. The efficiency of reburn technology for NOx reduction in oxide-fuel combustion under a flue gas recirculated (FGR) atmosphere was analysed. The present paper demonstrates the importance of the use of low-NOx burners with the reburn technology to minimise NOx emissions. The use of FGR or steam in reburn injection to increase the inlet momentum can produce differences in NOx reduction and these differences were analysed. The work shows the importance in developing mechanisms to couple efficiently the CFD models with the detailed chemical kinetic schemes, to predict NOx reduction under reburning conditions in full-scale boilers.