As a distinct socially constructed genre, wedding invitations (WIs) offer a fruitful site for investigating how two areas of genre knowledge (i.e., form and content) change over time under the influence of sociocultural forces. Through the examination of 100 Iranian WIs dating from 1970s to the present time, the study investigated the trajectories of change through time within the social semiotics framework. Findings revealed that although the generic structures of Iranian WIs have remained the same, their mode contents have undergone remarkable changes across time. These changes are discernable in the nonverbal features of color, size, design, and typography as well as the verbal features including text length, formality, reference terms, and mood. Findings suggest that in today’s sociocultural climate of Iran, creativity prevails over conventionalization, informality is favored over formality, and solidarity tends to replace power in the hierarchical dimensions of gender differentials and parental domination.