PCT No. PCT/FR95/00914 Sec. 371 Date Feb. 28, 1997 Sec. 102(e) Date Feb. 28, 1997 PCT Filed Jul. 7, 1995 PCT Pub. No. WO96/02655 PCT Pub. Date Feb. 1, 1996Compositions containing one or more nucleic acids and cationic polymers, and their use in gene therapy, particularly for in vivo nucleic acid transfer.