Offseason
- October 25, 1977: The Cardinals traded a player to be named later to the San Francisco Giants for Frank Riccelli. The Cardinals completed the deal by sending Jim Dwyer to the Giants on June 15, 1978.
- December 8, 1977: Dave Rader and Héctor Cruz were traded by the Cardinals to the Chicago Cubs for Jerry Morales, Steve Swisher, and cash.
- February 2, 1978: Ken Rudolph was signed as a free agent by the Cardinals.
- March 15, 1978: Rick Bosetti was traded by the Cardinals to the Toronto Blue Jays for Tom Bruno and cash.
Read more about this topic: 1978 St. Louis Cardinals Season