Content: Optical single-molecule detection at room temperature / Alfred J. Meixner — Pressure-tuning photochemistry of metal complexes in solution / Rudi Van Eldik and Peter C. Ford — Photo-induced and spontaneous proton tunneling in molecular solids / H. Peter Trommsdorff — The EPR spectroscopic D parameter of localized triplet diradicals as probe for electronic effects in benzyl-type monoradicals / Waldemar Adam ... [et al.] — Photothermal studies of photophysical and photochemical processes by the transient grating method / Masahide Terazima