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In new cosmological galaxy surveys like Euclid and LSST, the workhorse probe of dark energy are the “3x2pt” statistics of galaxy clustering, cosmic shear, and their cross-combination. I present recent work on adapting angular power spectra to the challenges of 3x2pt measurements under the stringent statistical requirements of these surveys. This includes new methods for measuring spectra from discrete observations, the treatment of shot noise, covariance estimation, and the estimation of full-sky spectra from partial-sky observations.