This book mainly provides readers with stochastic and statistical properties of conditional order statistics and conditional spacings as well as some stochastic properties of load-sharing systems. The conditional lifetime is widely used in survival analysis and reliability-related areas, and the conditional spacing is very important in goodness-of-fit, Type-II censoring and life tests etc.. Although the main focus in the text is on this crucial characteristic, our presentation cannot be restricted to conditional order statistics, conditional spacing and load-sharing system analysis alone, other important reliability and corresponding ordered properties are studied as well. This book offers a comprehensive treatment of different reliability models focusing on properties of the residual life and conditional spacing of coherent systems and load-sharing systems. Our presentation combines classical and recent results of other authors with our research findings of the last fifteen years. The book is mostly targeted at researchers and engineers related to reliability theory and engineering, can be applicable as reference for both at senior undergraduate and graduate level. The results obtained can be used as a supplement and extensions and generalizations to reliability theory and practical reliability studies as well as related fields. Moreover, most of them may be regarded as technical support for engineering designers to design better products with higher reliability performance.