Proposed herein book is devoted to the general problem of drilling efficiency by drilling equipment optimization. This book presents succinct statistical data on drill bit and drill cutter performance, as well as drilling equipment simulations. It covers the following:- methodological and practical issues of drilling performance regressions (rate of penetration, no-failure operation possibility) based on drilling statistics;- development drill cutter wear probabilistic models based on experimental data;- rock reaction force refer to PDC drill bit design;- drilling pipe reliability refer to its loading.