The contradiction between structure of requirements and structure of library stocks leads to the disproportion in a library science which is shown in weak use of funds and incomplete satisfaction of information requirements.
In the first case it is necessary to make active the recommendation of documents to expand reader's inquiry. In the second – it is expedient to contribute documents to exchange and reserve fund, to redistribute between libraries or to send to depositaries.
The contingent of readers, stream of inquiries, economic and social profile of the served zone, condition of information streams and the markets, funds of nearby libraries, etc. belong to the second group of factors of influence on formations of library stocks.
Similarly and formation influences use of library stocks not directly, and through reader's demand which in a sense precedes their use. Therefore, the reader's inquiry is a need for funds, and their use – satisfaction of reader's demand.
If violation of compliance between reader's inquiry and funds is expressed in excessive increase in the low-asked and not used documents, it is necessary to allocate the profile, not lost information values and documents, outdated, non-core for this library.
Follows from interrelation of reader's inquiry and library stocks that they keep the relative independence which is shown that their volume and structure not always coincide. Possibility of such discrepancy is caused by a contradiction between information requirements and library stocks. Information requirements of society continuously increase.