A method for producing alkylphosphonic acids, esters and salts, which comprises a) reacting a phosphinic acid source with olefins in the presence of a catalyst A to form an alkylphosphonous acid, salt or ester b) reacting the resulting alkylphosphonous acid, salt or ester with an oxidant or with an oxidant and water, wherein the oxidants are manganese dioxide, chromium trioxide, potassium dichromate, pyridine dichromate, pyridine chlorochromate, Collins reagent, Jones reagent, Corey-Gilman-Ganem reagent, (Dess-Martin)periodinane, o-iodoxybenzoic acid, ruthenium tetroxide, ruthenium dioxide, tetra-n-propyl perruthenate, ruthenium trichloride/sodium periodate, ruthenium dioxide/sodium periodate, hypochlorite, peracids and/or peroxo compounds, to form the alkylphosphonic acid derivative or the alkylphosphonous acid, salt or ester obtained after step a) and/or the alkylphosphonic acid, salt or ester obtained after step b) and/or the particular resulting reaction solution thereof are esterified with an alkylene oxide or an alcohol M-OH and/or M'-OH, and the respectively resulting alkylphosphonous ester, and/or alkylphosphonic ester are subjected to the further reaction step b), where R 1, R 2, R 3, R 4 are identical or different and are each independently H, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl and/or phenyl, and X and Y are identical or different and are each independently H, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, phenyl, ethylene glycol, propyl glycol, butyl glycol, pentyl glycol, hexyl glycol, allyl and/or glycerol, and/or Mg, Ca, Al, Sb, Sn, Ge, Ti, Fe, Zr, Zn, Ce, Bi, Sr, Mn, Cu, Ni, Li, Na, K and/or a protonated nitrogen base and the catalysts A and B comprise transition metals and/or transition metal compounds and/or catalyst systems composed of a transition metal and/or transition metal compound and at least one ligand. a) reacting a phosphinic acid source with olefins in the presence of a catalyst A to form an alkylphosphonous acid, salt or ester b) reacting the resulting alkylphosphonous acid, salt or ester with an oxidant or with an oxidant and water, wherein the oxidants are manganese dioxide, chromium trioxide, potassium dichromate, pyridine dichromate, pyridine chlorochromate, Collins reagent, Jones reagent, Corey-Gilman-Ganem reagent, (Dess-Martin)periodinane, o-iodoxybenzoic acid, ruthenium tetroxide, ruthenium dioxide, tetra-n-propyl perruthenate, ruthenium trichloride/sodium periodate, ruthenium dioxide/sodium periodate, hypochlorite, peracids and/or peroxo compounds, to form the alkylphosphonic acid derivative or the alkylphosphonous acid, salt or ester obtained after step a) and/or the alkylphosphonic acid, salt or ester obtained after step b) and/or the particular resulting reaction solution thereof are esterified with an alkylene oxide or an alcohol M-OH and/or M'-OH, and the respectively resulting alkylphosphonous ester, and/or alkylphosphonic ester are subjected to the further reaction step b), where R 1, R 2, R 3, R 4 are identical or different and are each independently H, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl and/or phenyl, and X and Y are identical or different and are each independently H, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, phenyl, ethylene glycol, propyl glycol, butyl glycol, pentyl glycol, hexyl glycol, allyl and/or glycerol, and/or Mg, Ca, Al, Sb, Sn, Ge, Ti, Fe, Zr, Zn, Ce, Bi, Sr, Mn, Cu, Ni, Li, Na, K and/or a protonated nitrogen base and the catalysts A and B comprise transition metals and/or transition metal compounds and/or catalyst systems composed of a transition metal and/or transition metal compound and at least one ligand.