Abstract: A modular millwork finishing or trim kit is provided. The modular finishing kit can include a trim unit and a set of connectors or retaining means. The trim unit can be shaped to outline an opening, for example, a window opening. The set of connectors can include one retaining means mounted to the window frame and/or rough opening. Another compatible retaining means can be mounted to the millwork trim kit. In operation, the retaining means attached to the millwork trim kit can facilitate removable, or permanent, engagement to the compatible retaining means positioned on the window frame and/or rough opening.