Waveform tomography - Successes, Cautionary tales, and future directions

I would like to highlight some of the issues in evaluating the success (or otherwise) of<br>waveform tomography. For synthetic data it is always tempting to commit inverse crimes, for<br>real data a scrutiny of the detailed data fit is "sine qua non". I'll go through some new<br>animations that illustrate the benefits of the frequency domain, and I'll finish with some topics<br>that we are working on - real data examples of Q-inversion being a current interest.