Dear Colleagues, It is our great pleasure to welcome you to CAMAD2016, the 21st International Workshop on Computer-Aided Modeling Analysis and Design of Communication Links and Networks, in Toronto, ON, Canada. The International Workshop on Computer-Aided Modeling Analysis and Design of Communication Links and Networks (CAMAD) was launched in 1986, targeting to provide a forum for discussion of recent developments on analytical and simulation tools and techniques for the performance evaluation of communications systems. It was held every 2 years until 2006, and yearly ever since, motivated by the ever increasing interest in this hot research and development field. Since 2009 CAMAD has been sponsored by the IEEE Communications Society. IEEE CAMAD 2016 will be held as a stand-alone event on 23-25 October 2016, at Ryerson University in Toronto, Ontario, Canada. IEEE CAMAD will focus on Communications for Smart Cities this year. IEEE CAMAD will be hosting several special sessions, and will bring together scientists, engineers, manufacturers and service providers to exchange and share their experiences and new ideas focusing on research and innovation results under wireless communications in smart cities. Looking forward to welcoming you in Toronto. Best regards, Jelena Misic and Burak Kantarci CAMAD 2016 General Chairs