That whether expansionary government spending crowds out private consumption is examined by evaluating the intra-temporal elasticity of substitution between them. Using annual data (1981-2000) of 23 OECD countries, a linear deterministic cointegration relation between private consumption, government spending and their relative price is supported. We have two findings: first, the panel estimators plausibly compute the parameter estimates in general. Second, when cross-sectional correlation is considered by using a SUR estimator, the statistical significance of panel cointegration is improved. Thirdly, the intra-temporal elasticity of substitution indicates that government and private consumption are found to be complements, which shows that expansionary government spending does not crowd out private consumption. (C) 2005 Board of Trustees of the University of Illinois. All rights reserved.