There have been a lot of baseball card sets that have been issued ever since they started making baseball cards all those years ago.  These sets vary in card amount and value.  Some of these many sets are classified as "condition sensitive".  This means that they are easier to damage than other card sets, therefore having a "condition sensitive" card or set in gem mint condition could be worth a lot of money.  I have consulted with numerous experienced collectors and have been able to compile the following list of the most "condition sensitive" baseball card sets.

• 1971 Topps
• Any set, new or old with black boarders
• 1987 Donruss
• Any Die-Cut cards or Diamond Kings framed cards
• 1993 Upper Deck SP
• 1963 Topps
• 1970 Topps
• 1975 Topps
• Kellogg's 3-D sets
• 1988 Donruss
• 1910 T205
• 1955 Bowman
• 1962 Topps
• 2004 Bowman's Best
• 1999 Upper Deck Ultimate
  
• 1895 n300 Mayo's cut plug
• Ramlys
• T3
• any prewar cabinets
• 1994 Upper Deck SP
• 2000 Upper Deck SPx
• 2000 Bowman Draft Picks Autographs w/ black borders
• 1952 Topps
• any original Old Judge cards
• 1909-1911 T206
• 1955 Topps
• 1968 Topps
• 1989 Bowman Tiffany
• 1985 Topps Tiffany
• 1989 Topps Tiffany
• 1992 Desert Storm
• 1995 Bowman's Best Refractors
• Any Bowman Chrome or Bowman Chrome Draft Picks
• T-205 Gold Borders