Differences between the First and Second Editions:
The First Edition cover is significantly different. No Paranoia Press banner or logo, a different illustration, and a price of $3 in the upper right corner.
In the First Edition, the letter from Marc Miller has a red stripe on it, the Second Edition is monochrome.
The credits page is relocated to before the Marc Miller letter in the First Edition and has a different mailing address.
The Scout Service Insignia preceding page 1 in the Second Edition is not included in the First Edition.
There are major differences in the Scout and Assassin character generation systems, as well as in the Unfit for Service survival resolution system.
The illustration on page 7 is different and credited to Gregg Bender in the First Edition, Steve Eden in the Second Edition.
The Type "S" Scoutship Serpent Class deckplan is monochrome with a 1979 date in the First Edition, two color with a 1981 date in the Second Edition.
The First Edition includes a two color Delta Research booklet with company information, details of the Serpent class Scoutship, a list of all Serpent class ships built, and a TAS Form 2 for the founder of Delta Research, "Storm".
this is the Second Edition entry Scouts & Assassins (Second Edition)
Scouts & Assassins, 2nd Edition
First Printing, April 1981 (note has a S&A 2nd Edition Errata sticker on inside cover)