It is the task of the BIPM to ensure worldwide uniformity of measurements and their traceability to the International System of Units (SI).

BIPM does tIt is the task of the BIPM to ensure worldwide uniformity of measurementshis with authority of the Convention of the Metre, a diplomatic treaty between fifty-one nations, and it operates through a series of Consultative Committees, whose members are the national metrology laboratories of the Member States of the Convention, and through its own laboratory work.

The BIPM carries out measurement-related research. It takes part in, and organizes, international comparisons of national measurement standards, and carries out calibrations for Member States.

The Convention of the Metre (Convention du Mètre)
The Convention of the Metre is a diplomatic treaty between fifty-one nations which gives authority to the Conférence Générale des Poids et Mesures (CGPM), the Comité International des Poids et Mesures (CIPM) and the Bureau International des Poids et Mesures (BIPM) to act in matters of world metrology, particularly concerning the demand for measurement standards of ever increasing accuracy, range and diversity, and the need to demonstrate equivalence between national measurement standards.

Representatives of seventeen nations signed the Convention in Paris in 1875. As well as founding the BIPM and laying down the way in which the activities of the BIPM should be financed and managed, the Metre Convention established a permanent organizational structure for member governments to act in common accord on all matters relating to units of measurement.

The Convention, modified slightly in 1921, remains the basis of all international agreement on units of measurement. There are now fifty-one Member States, including all the major industrialized countries.