Abstract: The present invention makes available methods and reagents for forming support-bound probes, particularly surface bound arrays of molecules, such as nucleic acids, peptides, proteins, small molecules, or other compounds of interest. The method generally involves providing an oligonucleotide bound to the surface of a solid support, hybridizing to the oligonucleotide a complementary sequence covalently linked to a molecule of interest (such as a probe nucleic acid, a peptide, a protein, a small molecule, etc.), and forming a covalent bond between the complementary sequence and the oligonucleotide or the surface of the solid support.