This volume collects refereed contributions based on the presentations made at the Sixth Workshop on Advanced Mathematical and Computational Tools in Metrology, held at the Istituto di Metrologia “G. Colonnetti” (IMGC), Torino, Italy, in September 2003. It provides a forum for metrologists, mathematicians and software engineers that will encourage a more effective synthesis of skills, capabilities and resources, and promotes collaboration in the context of EU programmes, EUROMET and EA projects, and MRA requirements. It contains articles by an important, worldwide group of metrologists and mathematicians involved in measurement science and, together with the five previous volumes in this series, constitutes an authoritative source for the mathematical, statistical and software tools necessary to modern metrology.The proceedings have been selected for coverage in:Index to Scientific & Technical Proceedings® (ISTP® / ISI Proceedings)Index to Scientific & Technical Proceedings (ISTP ROM version / ISI Proceedings)CC Proceedings — Engineering & Physical SciencesContents:Processing the Coherent Anomalies on Digitalized Surfaces in Wavelet Domain (P Ciarlini & M L Lo Cascio)Least Squares Adjustment in the Presence of Discrepant Data (M G Cox et al.)Some Differences between the Applied Statistical Approach for Measurement Uncertainty Theory and the Traditional Approach in Metrology and Testing (C Perruchet)Compound-Modelling of Metrological Data Series (F Pavese)Validation of Calibration Methods — A Practical Approach (E Filipe)A Hybrid Method for (ℓ1 Approximation (D Lei & J C Mason)A New Off-Line Gain Stabilisation Method Applied to Alpha-Particle Spectrometry (S Pommé & G Sibbens)Development of Software for ANOVA that Can Generate Expressions of Variance Expectations (H Tanaka et al.)Short Course on Uncertainty Evaluation (M G Cox)Software Requirements in Legal Metrology: Short Course Held Adjacent to the Conference (D Richter)and other articlesReadership: Researchers, graduate students, academics, professionals and industrialists in metrology.