Reuben holds a University Degree in Biology from Southampton University, and a Ph.D. in plant genetics, biochemistry and plant pathology from Imperial College, University of London. Reuben started his professional career in 1999 as volunteer in FAO HQ, in 2000 he became a consultant in the Global Terrestrial Observing System (GTOS) secretariat, were tasks included the development of international remote sensing and in situ standards for the measuring of the terrestrial climatic variables. Reuben worked in both the offices of the Director of NRC and the ADG of natural resources were he supported FAO work on climate change and the environment including FAO engagement to the UNFCCC, Rio+20 and other international related platforms. In 2010, Reuben coordinated the development of the original climate smart agriculture concept and led the process and was editor of the FAO CSA source book.
In May 2015, under the cooperate mobility plan, Reuben was appointed as climate change, DRR and energy coordinator for Europe and Central Asia in the Budapest office. Under his new role tasks include developing new programmes in the different sub-regions, providing technical and strategic guidance, as well as coordinating REU work and capacity building activities on the Green Climate Fund (GCF), Sendai Framework for Disaster Risk Reduction and the UNFCCC Paris agreement. Reuben is also alternative focal point in REU for SP5.