  We consider quantum graphs with transparent branching points. To design such
networks, the concept of transparent boundary conditions is applied to the
derivation of the vertex boundary conditions for the linear Schrodinger
equation on metric graphs. This allows to derive simple constraints, which use
equivalent usual Kirchhoff-type boundary conditions at the vertex to the
transparent ones. The approach is applied to quantum star and tree graphs.
However, extension to more complicated graph topologies is rather straight
forward.
