We report submilliarcsecond-precise astrometric measurements for the late-type star AB Doradus via a combination of VLBI (very long baseline interferometry) and HIPPARCOS data. Our astrometric analysis results in the precise determination of the kinematics of this star, which reveals an orbital motion readily explained as caused by gravitational interaction with a low-mass companion. From the portion of the reÑex orbit covered by our data and using a revised mass of the primary star (0.76 M _) derived from our new value of the parallax (66.3 mas \ n \ 67.2 mas), we Ðnd the dynamical mass of the newly discovered companion to be between 0.08 and 0.11 If accurate photometric information can M _. be obtained for the low-mass companion, our precise mass estimate could serve as an accurate calibration point for di †erent theoretical evolutionary models of low-mass objects. This represents the Ðrst detection of a low-mass stellar companion using VLBI, a technique that will become an important tool in future searches for planets and brown dwarfs orbiting other stars.

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The sheer volume of decisions taken within the public sector procurement process prevents perfect and complete information being obtained and applied to every best value tender analysis that is carried out. As such, uncertainty must be accepted as a feature of the best value decision-making process. • This paper reports research which is developing a methodology for utilising the uncertainty component in best value tender analysis in order to create a more transparent decision making process.• The main output of the research is the production of a robust support tool which aids the multi objective decision making process within the public sector of the UK construction industry by provoking rational discussion with respect to; the industry's key performance indicators (KPIs), the client's attitude to risk and provides a transparent audit trail of the decisions taken.• The underlying rationale for the support tool is based on a combination of the Analytic Hierarchy Process (AHP), Multi-Attribute Utility Theory (MAUT) and Whole Life Costing (WLC). The paper demonstrates the practical utility of the methodology of the tool through a tender decision process.

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