Power-dividing and/or power-combining circuits have inputs, outputs, and at least three electrical pathways, with substantially equal input and output reflection coefficients. An electronic device may be provided in each of the pathways. Additionally, isolation circuits or devices can be inserted between signal lines to provide isolation between inputs, in the case of combining, or outputs, in the case of dividing. In one embodiment, multiple phase shift components are electrically connected to electronic devices in the electrical pathways. These phase shift components are selected so that a vector sum of the reflected signals from the inputs in combining and/or to the outputs in dividing is substantially minimized.