Studies of the ISM in the Vela supernova remnant

Recent observations of the Vela SNR in the ISM species Ca II and Na I are p resented and discussed in the context of the "break-down'' of the Spitzer-R outly effect. Variations in line profiles with time are demonstrated, event ually through a statistical approach a description of cloud structure will be possible. The IS lines in similar to 70 sightlines are used to determine an accurate distance to the Vela SNR of 250 +/- 30 pc. Finally a discussio n of future observations are given relating information obtained from measu rements of near-by ISM to more distant intergalactic medium.