The state of the art and major trends in monocarbon molecule transformation chemistry were reviewed, with particular reference to transformations of methane into petrochemicals and fuels. Poland's research program continued since 2001 "The C-1 Chemistry - Processes of Chemical Transformation of Methane (Natural Gas)" (PBZ/KBN/018/T09/99) was presented together with the course of the studies and the results achieved so far.