The proceedings of NUMDIFF-15 will be published as a special issue of the Journal of Computational and Applied Mathematics. Guest editors are the members of the scientific committee and the managing guest editor is Jens Lang. Every speaker of NUMDIFF-15 can submit a manuscript for consideration of publication in this special issue. Submitted manuscripts must deal with original work not published elsewhere and will be refereed according to the standard journal procedure. For a statement of the journal’s objectives and the instructions for authors, see: http://www.journals.elsevier.com/journal-of-computational-and-applied-mathematics Authors are encouraged to use the journal style files. The paper length is restricted to 20 style file pages. The deadline for manuscript submission is 10 January 2019. The manuscripts should be submitted through http://ees.elsevier.com/cam/. Please indicate that your article is for this special issue by selecting article type “NUMDIFF15”. Please also send a copy directly to lang@mathematik.tu-darmstadt.de.