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tokens: A typical peculiar velocity of 300 km s −1 equates to a proper motion of 6.3 μ as yr −1 at 10 Mpc. A sample of objects with proper motion uncertainty σ μ = 100 μ as yr −1 would require roughly 250 independent measurements to reach this proper motion value and roughly 2300 measurements to achieve 3 σ significance. Such averaging to reduce statistical errors would only be possible if one knew a priori the orientation of each proper motion vector in the sample. Since this is not known, it is appropriate to examine the correlation of extragalactic pairs. Since the number of galaxies in a volume scales as N ∝ D 3 , and the number of possible pairs scales as , then the number of pairs scales as N p ∝ D 6 . The uncertainty in the transverse velocity correlation scales as . Using Equation ( 60 ), and assuming that the fractional proper motion uncertainty is much larger than the distance uncertainty, . The uncertainty in the correlation therefore scales roughly as . This relationship assumes that x / D ≲ 1, that pairs represent independent measurements of the peculiar velocity field (not strictly true), that the proper motion measurements in value and uncertainty are uniform among the sample, and it neglects the random orientations of pairs. Including these effects will impact the constant of proportionality and may diminish the favorable impact of distance on the uncertainty in the measured correlation statistic. The optimal strategy for measuring the transverse peculiar velocity created by large-scale structure will depend on the data in hand: the redshift distribution, pair separations, sample size, and proper motion precision. VLBI proper motions will likely have redshifts of z ∼ 1, proper motion uncertainties per object of σ μ ∼ 10 μ as yr −1 , and sample sizes of 500–1000 objects (e.g., Darling 2013 ; Truebenbach Darling 2017 ). Gaia AGN proper motions will have lower redshifts, smaller pair separations, and sample size ∼10 5 , but larger per-object proper motion uncertainties of ∼200 μ as yr −1 (e.g., Paine et al. 2018 ; Truebenbach Darling 2018 ). 6. Conclusions and Future Work We have developed two-point transverse peculiar velocity correlation statistics that connect the matter power spectrum to extragalactic proper motions. We have explored the impact of pair separation, distance, and angular separation on these correlations and suggested some strategies for future extragalactic proper motion surveys. Except for very nearby pairs of objects that subtend large angles, close pairs are more sensitive to large-scale structure than widely separated pairs, as one might expect. We develop correlation statistics for randomly oriented pairs of objects with various separation-to-distance ratios. Finally, we suggest that the sensitivity to the transverse velocity correlation improves with distance in volume-limited surveys, but the optimal detection strategy will depend on the nature of the proper motion data in hand. The work presented here has