El primer trailer de Star Wars

With the production in a mad rush to finish the special effects, Charles Lippincott was busy promoting the movie at conventions and by other means like the novelization and the Marvel comic that was in development. One of the other tools in his shed was the first teaser trailer. Lippincott met with Lucas, Kurtz, assistant optical editor Bruce Green and three ad agency people in November 26, 1976, to talk about the trailer’s storyboard and everything that was needed to make a rough cut. This was finished a mere three days later and talks began about what needed to be changed and what music would be heard in the trailer.

In the next couple of weeks, Bruce Green would travel back and forth between ILM and MFE (Modern Film Effects — the company responsible for the effects of the trailer like the exploding logo) to get the teaser ready. It was fully approved by Lucas in early December and ready for review by Fox. However, tensions were high due to the troublesome production that the movie had up to this point, and the executives were far from pleased with a teaser that featured a couple of unfinished shots and was seen by Lucas and his team as a “spirit of the movie” trailer. Fox even went as far as trying to change the title of the movie, but that never happened because nobody ever gave Lucas acceptable title alternatives. The teaser was finally released in cinemas during the Christmas season, and receptions were a bit of a mixed bag with some people becoming curious for the movie while critics said it would never work.

Source:
http://www.starwars.com/news/star-wars-trailers-part-1-the-original-trilogy