INTRODUCTION: The National Institutes of Health Stroke Scale (NIHSS), the most commonly used tool to quantify neurological deficit in acute stroke, was initially developed in English. We present our experience in developing and validating an Arabic version of the NIHSS (arNIHSS). METHODS: RESULTS: In 6months, 137 patients were recruited (mean age+/-standard deviation 62+/-12years; 48 women). For interrater agreement, weighted kappa value ranged from 0.36 to 0.66 and intraclass correlation coefficient (ICC) for the whole scale was excellent at 0.95 (95% confidence interval [CI] 0.94-0.97). For intrarater agreement, weighted kappa ranged from 0.52 to 1.0 and the ICC was 0.94 (95% CI 0.87-0.98). The construct validity of the arNIHSS is demonstrated by its correlation with the DWI-ASPECT and the 3months mRS score (Spearman correlation -0.46 and 0.58 respectively; P<0.001 for both). CONCLUSION: We developed and validated a culturally adapted Arabic version of the NIHSS. Further validation in other Arab countries is recommended.