Spatial measurements of ocean surface waves provide direct wavenumber resolution of the wave spectrum. This is advantageous in avoiding the problems associated with doppler frequency shift in the case of small scale surface roughness studies in relation to ocean remote sensing. If the spatial measurements cover the 2D (x, y) plane, the directionality of the wave field can be derived straightforwardly. The processing of 2D images, however, is still limited by the 180-degree ambiguity due to the axi-symmetric property of Fourier analysis, and may hamper our ability to distinguish between left-right and front-back propagation of the wave components. The ambiguity can be avoided by 3D (x, y,t) measurements, which produce the complete 3D (kx, ky, ω) spectrum. Examples of 1D, 2D and 3D spatial measurements of surface waves will be presented. The resolved wavelength ranges from 4 millimeters (laser scanning slope sensor) to hundreds of meters (airborne scanning lidar system). Some interesting results derived from spatial measurements include the wavenumber properties of short waves that are important to quantification of the ocean surface roughness, delicate difference in the interpretation of dispersion relation derived from spatial and temporal measurements, bimodal directional distribution of surface waves in equilibrium range that illustrates the role of nonlinear wave-wave interaction in the evolution of surface wave dynamics, and bimodal directional distribution of young waves that poses questions on our present interpretation of the wind wave generation mechanisms.