In the Literature, Several Correlations Have Been Proposed for Gas Holdup Prediction in Bubble Columns. However, These Correlations Fail to Predict Gas Holdup over a Wide Range of Conditions. based on a Databank of Around 3500 Measurements Collected from the Open Literature, a Correlation for Gas Holdup Was Derived using a Combination of Dimensional Analysis and Artificial Neural Network (ANN) Modeling. the overall Gas Holdup Was Found to Be a Function of Four Dimensionless Groups: Reg, Frg, Eo/Mo, and Ρg/ρL. Statistical Analysis Showed that the Proposed Correlation Has an Average Absolute Relative Error (AARE) of 15% and a Standard Deviation of 14%. a Comparison with Selected Correlations in the Literature Showed that the Developed ANN Correlation Noticeably Improved Prediction of overall Gas Holdup. the Developed Correlation Also Shows Better Prediction over a Wide Range of Operating Conditions, Physical Properties, and Column Diameters, and It Predicts Properly the Trend of the Effect of the Operating and Design Parameters on overall Gas Holdup. © 2003 Elsevier Science B.V. All Rights Reserved.