This document is used as a guidance that applies to hydroelectric installations containing impulse or reaction turbines with unit power up to about 15 MW and reference diameter of about 3 m. These figures do not represent absolute limits. This document deals only with the direct relations between the purchaser or the consulting engineer and the supplier. It does not deal with civil works, administrative conditions or commercial conditions. This document is intended to be used by all concerned in the installation of electromechanical equipment for small hydroelectric plants. This document, based essentially on practical information, aims specifically at supplying the purchaser of the equipment with information which will assist him with the following: preparation of the call for tenders; evaluation of the tenders; contact with the supplier during the design and manufacture of equipment; quality control during the manufacture and shop-testing; follow-up of site erection; commissioning; acceptance tests; operation and maintenance. The document comprises the following: a)general requirements for the electromechanical equipment of small hydroelectric installations; b)technical specifications for the electromechanical equipment, excluding its dimensioning and standardization; c)requirements for acceptance, operation and maintenance. Bearing in mind the type of installation considered, the necessary documents are intended to be as simple as possible but to satisfactorily define the particular operation conditions. Over-specification is harmful to the economy of the project. This document does not cover the initial stage of investigations, that is to say the preliminary study and feasibility study. Neither does it deal with the economic study concerning the supply and demand of energy. To conclude, the document does not replace the necessary engineering studies for the selection, design, manufacture, installation and testing of the equipment. It is intended only to make the purchaser aware of the important points and data to be furnished, specified and kept in due consideration in the construction of small hydroelectric plants.