In this exciting era of "next-gen cytogenetics", the use of novel molecular methods such as comparative genome hybridization and whole genome and whole exome sequencing becomes more and more common in clinics. This results in generation of large amounts of high-resolution patient-specific data and challenges the development of new approaches for interpretation of obtained information. Usually, interpretation of chromosomal rearrangements is focused on alterations of linear genome sequence, underestimating the role of spatial chromatin organization. In this article, we describe the main features of 3-dimentional genome organization, emphasizing their role in normal and pathological development. We highlight some tips to help physicians estimating the impact of chromosomal rearrangements on the patient phenotype. A separate section describes available tools that can be used to visualize and analyze human genome architecture.