A method for correcting positioning data, supplied by a first platform (V 1), provided with a first geometric reference frame (R G1), to a second platform (V 2), provided with a second geometric reference frame (R G2), the two platforms being positioned such that they have a common area of land in their field of observation, in which method the absolute locations and the attitude angles of the platforms (V 1) and (V 2) in a land reference frame (R Ter) are known to within any measurement errors, which method is characterized in that: - the positions in the absolute land reference frame (R Ter) of a first group (A 1) of N landmarks present on the land and seen from the first platform (V 1) are calculated at the first platform (V 1), then transmitted to the second platform (V 2), which positions are called absolute positions P A1 (i), i varying from 1 to N; - the positions in the absolute land reference frame (R Ter) of a second group (A 2) of M landmarks present on the land and seen from the second platform (V 2) are calculated at the second platform (V 2), which positions are called absolute positions P A2 (j), j varying from 1 to M; - at the second platform (V 2), an optimization algorithm is implemented which is applied to a change of reference frame C(T,RO 2), which algorithm, by performing an incremental optimality search, successively causes the absolute positions P A1 (i) of the first group of landmarks (A 1) to pivot by the rotation angles R about the origin (O 2) of the second geometric reference frame (R G2), then to translate by a translation vector T, according to successive increment steps of decreasing sizes, and determines, for each increment step of the optimization algorithm, a position, called estimated position P eA1, of each landmark of the first group of landmarks (A 1), namely P eA1 (i) for i varying from 1 to N, and calculates, for each increment step of the optimization algorithm, a proximity criterion Q between the absolute positions P A2 (j) of the landmarks of the second group (A 2) and the estimated positions P eA1 (i) of the landmarks of the first group (A 1); - the optimization algorithm is stopped when the current increment steps of the optimization algorithm no longer lead to improving the proximity criterion Q or when they are below preset values, values which have been chosen to correspond to the desired location precision; - the rotation R opt and translation T opt values of the optimal reference frame change C opt having led to the desired precision are stored; - at least one absolute position information item supplied by the first platform (V 1) is corrected at the second platform (V 2) by applying the optimal reference frame change C opt to this position information item. - the positions in the absolute land reference frame (R Ter) of a first group (A 1) of N landmarks present on the land and seen from the first platform (V 1) are calculated at the first platform (V 1), then transmitted to the second platform (V 2), which positions are called absolute positions P A1 (i), i varying from 1 to N; - the positions in the absolute land reference frame (R Ter) of a second group (A 2) of M landmarks present on the land and seen from the second platform (V 2) are calculated at the second platform (V 2), which positions are called absolute positions P A2 (j), j varying from 1 to M; - at the second platform (V 2), an optimization algorithm is implemented which is applied to a change of reference frame C(T,RO 2), which algorithm, by performing an incremental optimality search, successively causes the absolute positions P A1 (i) of the first group of landmarks (A 1) to pivot by the rotation angles R about the origin (O 2) of the second geometric reference frame (R G2), then to translate by a translation vector T, according to successive increment steps of decreasing sizes, and determines, for each increment step of the optimization algorithm, a position, called estimated position P eA1, of each landmark of the first group of landmarks (A 1), namely P eA1 (i) for i varying from 1 to N, and calculates, for each increment step of the optimization algorithm, a proximity criterion Q between the absolute positions P A2 (j) of the landmarks of the second group (A 2) and the estimated positions P eA1 (i) of the landmarks of the first group (A 1); - the optimization algorithm is stopped when the current increment steps of the optimization algorithm no longer lead to improving the proximity criterion Q or when they are below preset values, values which have been chosen to correspond to the desired location precision; - the rotation R opt and translation T opt values of the optimal reference frame change C opt having led to the desired precision are stored; - at least one absolute position information item supplied by the first platform (V 1) is corrected at the second platform (V 2) by applying the optimal reference frame change C opt to this position information item.