1 Introduction Data extract from Landolt-Börnstein III/47: Optical Constants 1.1 Selection of data This supplement updates Landolt-Börnstein's New Series Group III (Condensed Matter) Volume 38, Op- cal Constants, published in two subvolumes in the year 1996 [1996WOH1, 1996WOH2]. The update p- vides experimental data published in the years 1995 to 2006. The ?nal date for including data was December, 31st, 2006. Specialization and selection of data for this new update follows the intentions of the original volume. The focus is on non-electrolyte systems, and only data for pure liquids and binary liquid mixtures at normal pr- sure (but in some single cases here also at higher pressure) were taken into account for this volume. For mixtures, this data collection is restricted to binary liquid mixtures, i.e. no ternary systems and also no so- tions of any solids, salts, electrolytes, polymers are included here. Surfactant solutions or micellar systems in water or other ?uids were not considered either. At least, also molten metals and metallic alloys, molten salts, molten glasses and other high-temperature melts were not taken into account. As the amount of data collected between 1995 and 2006 exceeds the available space for printing by far, the volume has an electronic version containing additional data which is available on www.landolt-boernstein.com.