%&tex
    \node (pd) {Problem Description};
    \node (sp)[below=1 of pd]  {System\\Requirements};
    \node (id)[below=1 of sp]  {Initial Design};
    \node (fs)[below=1 of id]  {Feature Definition};
    \node (ss)[below=1 of fs]  {Feature Selection};
    \node (a1)[below=0.8 of ss,draw=none, fill=none] {};
    \node (rd)[below=0.8 of a1]  {Rapid Development};
    \node (va)[right=1 of a1]  {Variable Approach};
    \path[->] (pd) edge (sp)
              (sp) edge (id)
              (id) edge (fs)
              (fs) edge (ss)
              (ss) edge (rd)
              (rd.east) edge[bend right] (va)
              (va) edge[bend right] (ss.east);