摘要:Foreword for the Proceedings of the International Congress in Honour of Professor Hari M. Srivastava. This article is being published in each of the four Special Issues of the SpringerOpen journals, Advances in Difference Equations, Boundary Value Problems, Fixed Point Theory and Applications and Journal of Inequalities and Applications, which are entitled ‘Proceedings of the International Congress in Honour of Professor Hari M. Srivastava’.