Monolithic stationary phases show promise for LC as a result of their good permeability, ease of preparation and broad selectivity.However, the performance of organic monoliths, in particular has generally not reached the level of particle packed columns, which can be attributed to their morphologies.Wide through-pore size distribution and variable skeletal lattice dimensions along the column length and across the column diameter reduce the column performance.Thus, domain, through-pore and mesopore sizes of the monolithic structures are important factors governing their performance.Fortunately, these factors can be optimized independently for monolithic columns in contrast to particle packed columns.Studying and characterizing the bed structures of organic monolithic columns can provide great insights into their performance, and aid in structure-directed synthesis of new and improved monoliths.