This study examined the effect of executive dominance on parliamentary committee effectiveness in Uganda, drawing on a cross-sectional survey of 312 respondents including members of parliament, committee clerks, civil society representatives, and parliamentary researchers. The study was anchored on the principal-agent theory and the separation of powers doctrine. Three specific objectives guided the inquiry: to assess the extent of executive dominance over parliamentary committees in Uganda; to examine the relationship between executive dominance and committee effectiveness; and to determine the effect of executive dominance on the oversight, legislative review, and budget scrutiny functions of parliamentary committees. A structured questionnaire measuring executive dominance across five dimensions budget control, appointment power, legislative agenda setting, information asymmetry, and party discipline and committee effectiveness across three sub-dimensions was administered. Data were analysed using univariate descriptive statistics, bivariate Pearson correlation, multiple linear regression, and structural equation modelling (SEM). Descriptive findings revealed a mean executive dominance composite score of 4.17 (SD=0.52) on a 5-point Likert scale, while the mean committee effectiveness score stood at a significantly lower 2.63 (SD=0.71), indicating constrained parliamentary performance. Pearson correlation analysis returned a strong negative association between executive dominance and committee effectiveness (r=−0.621, p