99mTe sestamibi and99mTc teboroxime has unique features that differ from thallium-201 in dosimetry, energy, cellular transport, extraction fraction, retention, washout, and imaging protocols. Sestamibi is ideal for gated and SPECT imaging while SPECT imaging with a multi-head detector system is preferred for teboroxime. Both permit simultaneous assessment of perfusion and function using first-pass radionuclide angiography. This paper discusses the special features and clinical applications of these two technetium agents. © 1992 Kluwer Academic Publishers.