Daniel ben–Avraham obtained his Ph.D. in Physics from Bar–Ilan University, Israel in 1985. After a 2 year Post-Doctoral position in the Center of Polymer Studies at the University of Boston, he gained a permanent position at Clarkson University where he is now Professor of Physics. Prof. ben–Avraham has spent time as Visiting Professor at various institutions including Heidelberg University, Bar–Ilan University and the European Center for Molecular Biology. He has published over 80 papers and contributed invited papers to several anthologies. Shlomo Havlin obtained his Ph.D. in 1972 from Bar–Ilan University. He stayed at Bar–Ilan University progressing through the ranks of Research Associate, Lecturer, Senior Lecturer and Associate Professor until in 1984 he became Professor and Chairman of the Department of Physics. He is currently Dean of the Faculty of Exact Sciences. Since 1978 Prof. Havlin has spent time as Visiting Professor at numerous institutions including the University of Edinburgh, the National Institute of Health (NIH) and Boston University. He is currently on the editorial board of 3 journals, author of over 400 papers, editor of 10 books and has given over 40 plenary and invited talks.