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We assess whether chondrules, once-molten mm-sized spheres filling the oldestmeteorites, could have formed from super-km/s collisions between planetesimalsin the solar nebula. High-velocity collisions release hot and dense clouds ofsilicate vapor which entrain and heat chondrule precursors. Thermal historiesof CB chondrules are reproduced for colliding bodies $\sim$10--100 km inradius. The slower cooling rates of non-CB, porphyritic chondrules point tocolliders with radii $\gtrsim$ 500 km. How chondrules, collisionally dispersedinto the nebula, agglomerated into meteorite parent bodies remains a mystery.The same orbital eccentricities and inclinations that enable energeticcollisions prevent planetesimals from re-accreting chondrules efficiently andwithout damage; thus the sedimentary laminations of the CB/CH chondriteIsheyevo are hard to explain by direct fallback of collisional ejecta. At thesame time, planetesimal surfaces may be littered with the shattered remains ofchondrules. The micron-sized igneous particles recovered from comet 81P/Wild-2may have originated from in-situ collisions and subsequent accretion in theproto-Kuiper belt, obviating the need to transport igneous solids across thenebula. Asteroid sample returns from Hayabusa2 and OSIRIS-REx may similarlycontain chondrule fragments.

Chondrules from high-velocity collisions: thermal histories and the agglomeration problem