The paper overviews the Linux Standard Base (LSB) open standard, which is becoming the main target for developing Linux applications. The standard itself is overviewed as well as its supporting infrastructure. Experience of the Institute for System Programming of RAS is given about developing LSB infrastructure and about working as a part of LSB international workgroup. LSB is developed by the international consortium Linux Foundation - the leading organization to foster the growth of Linux - supported by such companies as IBM, Intel, HP, Novell, Oracle and many others. The purpose of LSB is to prevent fragmentation of the Linux platform by standardizing Linux interfaces that are present in all major distributions and which application developers may rely on. LSB enables development cost reduction when targeting applications for "single Linux" rather than for particular distributions individually. A division of the Institute for System Programming of RAS - Linux Verification Center - is involved in developing LSB itself and in corresponding infrastructure activities such as testing Linux interfaces and developing informational systems and frameworks. The current results include new frameworks for automated test development of various "cost and value" grades, corresponding new tests for about 6000 of Linux interfaces, LSB Navigator - a web portal for LSB community and a new certification system.