Monoliths are here to stay.

It was again a pleasure for us to edit the already 4th special issue of Journal of Separation Science devoted to monoliths that continue to be a ‘‘hot topic’’. The specific subject covered by this issue relates in fact to monolithic materials or even more specifically, to monolithic materials used in the separation and related processes. Monoliths not only evoke a practical interest, they also force the scientists to think of them more thoroughly to gain a deeper understanding of structures and processes that enable to further extend their great potential. A large number of publications, patents, and presentations have already proven vitality of monoliths born in the late 1980s and early 1990s. Without doubt, this dating allows us to call the monoliths a recent development from the historical point of view but in terms of present dynamic reality, they are around for enough long time to count them as almost a classical subject. It appears that we already know quite a lot about monoliths including theory, preparation, formats, and applications. Several vendors are producing monolithic devices. However, this cannot let us think that ‘‘all has already been invented’’. Scientists always find serendipitous phenomena and applications making further studies rewarding. One more feature typical of monoliths should also be mentioned. In contrast to let us say packed columns, monoliths after the preparation step are not only ready-to-use materials, but they are in fact a ready-to-use devices in desirable size, shape, and format suitable for the required application. Thus, the preparation plays a key role in fabrication of final products and must be thoroughly studied and carefully optimized. This 4th special issue concerning monoliths that you hold in hand or see on the screen covers a variety of topics that span from the modeling, preparation and application of home-made monoliths, to applications of commercially available monolithic columns. Interestingly, quite significant number of papers concern capillary electrochromatography. Does it mean that we observe the comeback of CEC? Let us see. As always, both types of monoliths, silica, and organic-polymer-based ones are covered. While the former are mostly represented by commercial columns with a focus on applications, the latter, that embody most of the papers published in this issue, relate to both their preparation and application. Once again, the number of submitted manuscripts was large and their quality mostly excellent. This issue includes a record number of 50 papers. It is worth noting that we received a significantly higher number of manuscripts. Unfortunately, not all of these manuscripts have reached the level required for publishing in the Journal of Separation Science. However, all authors certainly deserve our thanks for both their manuscripts and for submitting them on time. We also know that the reviewers considerably contributed to the high quality of papers published in this issue. They deserve to be acknowledged for their helpful suggestions and comments as well as for speed they submitted their reviews. We hope that you will find this issue just as enjoyable as we do. For those who are already engaged in the ‘‘monolithic business’’ this issue may be a source of new ideas while the novices who did not ‘‘taste’’ the monoliths yet may found here an inspiration for their new projects.