The Higgs boson, the most recently discovered particle in the Standard Model, is predicted to be an elementary scalar boson which can interact with itself -- an interaction which has yet to be experimentally observed. Measuring the strength of the Higgs self-interaction could tell us if the Higgs is a composite particle, about the shape of the Higgs potential, and further illuminate the details of Electroweak Symmetry-Breaking. By searching for proton--proton collisions at the Large Hadron Collider which produce two Higgs bosons at the same time, we can directly probe the Higgs trilinear self-coupling. In this talk, I will motivate and present results from the latest ATLAS search for di-Higgs production in the HH→bbττ (two b-quarks and two tau leptons) decay channel, the most sensitive search of its kind to date, and the prospects for ATLAS di-Higgs measurements.