As frequencies approach 70 GHz or even 110 GHz, errors related to fixturing can be greater than those of the DUT. Fixtures and connectors to DUTs come in many forms. Poor de-embedding can lead to passivity and causality errors. Plus, high fixture loss may affect the accuracy and repeatability of de-embedding. Achieving accurate measurements at these higher frequencies offers the advantage of improved ability to locate discontinuities, impedance changes, and crosstalk issues. Newer more flexible and repeatability-tolerant methods of calibration and de-embedding techniques help resolve complex 28 Gbit/s problems. This white paper discusses the available de-embedding techniques and the tradeoffs between them.