This chapter proposes a distributed cooperative guidance law with guaranteed convergence in response to the inherently finite-time property of the guidance problem. First, a fixed-time convergent error dynamic is proposed based on a unified form of guidance problem. The ratio between the settling time upper bound and the whole guidance time is a constant less than 1 and independent of initial conditions. Then, the distributed cooperative guidance law with guaranteed convergence is developed based on the fixed-time convergent error dynamic and varying-gain PNG law. The command singularity issue is addressed by introducing an auxiliary function of the lead angle. Numerical simulations are provided to show the advantages and potential significance of the proposed results.