Recent experiments on decoherence rate in various mesoscopic systems  suggest a strong evidence for a non-thermal dissipation mechanism dominant at low temperatures. Keeping the anticipated consequences of such a mechanism in view, I first discuss the experiments in light of recent suggestions of mechanisms including two-level systems [2,3] or external high-frequency noise, to show that the observed trends cannot be reconciled with these suggestions. Then I discuss various aspects of the non-thermal low temperature decoherence [4,5]. In particular, the problem of the experimentally observed persistent current in normal metal rings is analyzed in the backdrop of a non-thermal decohering environment . Prospects for a conceptual understanding of the size of the current, observed in experiments, along with the sign are explored.
 P. Mohanty, E.M. Jariwala, R.A. Webb, Phys. Rev. Lett. 78, 3366
Fortschr. der Physik 46, 779 (1998).
 Y. Imry, H. Fukuyama, and P. Schwab, preprint cond-mat/9903017, to be published in Europhys. Lett. (1999).
 A. Zawadowski, J. von Delft, D.C. Ralph, preprint cond-mat/9902176.
 R. Raimondi, P. Schwab, and C. Castellani, preprint cond-mat/9903146, to be published in Phys. Rev. B (1999).
 P. Mohanty, E. M. Q. Jariwala, M. B. Ketchen, and R. A. Webb, in Quantum Coherence and Decoherence, edited by K. Fujikawa, and Y. A. Ono (Elsevier Science, 1996).
 P. Mohanty, Annalen der Physik 8, 549 (1999).