The crystal growth of CsSrBr 3 : Eu with improved energy resolution for use in gammaray detection applications is reported. CsSrBr 3 boules doped with 5% Eu were grown by the vertical Bridgman method in quartz ampoules of 17 mm and 22 mm diameter. It was observed 10 that the addition of an excess of CsBr in the melt improved the optical transparency and energy 11 resolution of the scintillator crystals. The energy resolution of the gamma-ray spectra recorded 12 with crystals measuring ø 22 mm × 15 mm was 7.4% at 662 keV (for a crystal with non-13 optimized stoichiometry) and 6.2% at 662 keV (for a crystal with optimized stoichiometry i.e. 14 excess CsBr in the melt), which is a significant improvement over previous reports. Temperature 15 dependent powder XRD measurements were also carried out to study the solid-solid phase 16 transition which occurs as the crystals are cooled after growth. 17 18 KEYWORDS-A2 Growth from melt, B1 Halides, B1 Rare earth compounds, B3 Scintillators.