I will discuss observational evidence suggesting the presence of high-velocity ejecta in the for of opposing jets in likely remnants of core-collapse SNe. I will concentrate on the bright radio and X-ray source Cassiopeia A (Cas A), the youngest known supernova remnant in the Milky Way, which shows optical jets of S-rich ejecta moving at10,000 - 15,000 km/s. While these jets are best seen in optical HST images, they are coincident with extended emission observed in both the X-rays and infrared.