In a burner (1) for a heat generator, having a throughflow passage (3) for the throughflow of a combustion-air flow (12), a hentral main fuel lance (5) acts inside the said throughflow passage (3). A number of mixing elements (6) are arranged in an annular manner around this main fuel lance (5), and the remaining annular throughflow cross section is covered concentrically hereto by swirl generators. The mixing elements (6) are fed with a fuel (13a) and a partial combustion-air quantity (12a). The mode of operation of these mixing elements (6) corresponds to that of a pilot stage, whereby the flame stability is increased, while the NOx emissions remain at a low level.