A conductive pattern is formed using a reactive polymer comprising pendant tertiary alkyl ester groups, a compound that provides an acid upon exposure to radiation, and a crosslinking agent. A polymeric layer is patternwise exposed to form first exposed regions with a polymer comprising carboxylic acid groups that are contacted with electroless seed metal ions, and then contacted with a halide to form corresponding electroless seed metal halide. Another exposure converts electroless seed metal halide to electroless seed metal nuclei and forms second exposed regions. A reducing agent is used to develop the electroless seed metal nuclei in the second exposed regions, or to develop the electroless seed metal halide in the first exposed regions. Fixing is used to remove any remaining electroless seed metal halide. The electroless seed metal nuclei are then electrolessly plated in various exposed regions.