We report spatially resolved laser-induced fluorescence (LIF) measurements of nitric oxide (NO) in a preheated, two-atmosphere, lean direct-injection (LDI) spray flame. The spray is produced by a hol-low-cone, pressure-atomized nozzle supplied with liquid heptane. NO is excited via the Q2(26.5) transition of the γ(0,0) band. Detection is performed in a 2-nm region centered on the γ (0,1) band. A complete scheme is developed by which quantitative NO concentrations in high-pressure LDI spray flames can be measured by applying linear LIF. Standard excitation and detection scans are performed to assess possible interferences and to verify a non-resonant wavelength for subtracting the influence of oxygen interferences and Mie scattering in the NO detection window. NO is doped into the reactants and convected through the flame with no apparent destruction, thus allowing an NO fluorescence calibration to be taken inside the flame environment. The in-situ calibration scheme is validated by comparisons to a reference flame. Relative axial calibration slopes are utilized in order to obtain radial profiles of absolute NO concentrations. These quantitative NO profiles are presented and analyzed so as to better understand the operation of lean-direct injectors for gas turbine combustors.