Nurses' abilities to effectively manage hospitalized patients' symptoms may be influenced by organizational factors on the nursing units, particularly the size of the nursing unit, work complexity and nurses' participation in decision making. Guided by Structural Contingency Theory (SCT) which assumes that structural forms and context must match in order for effectiveness to be achieved in organizations, this study assumes that achieving effective management of patient symptoms in hospitals depends on identification of nursing unit structures that are best suited to the technological contexts in which nursing units operate. The purpose of this study was to investigate the interrelationships among the nursing unit's context (unit size and work complexity), structure (nurses' participation in decision making) and effectiveness (symptom management). Mixed-effects linear models were used to test the data according to the hypothesized statements. The hypothesized relationship between increased unit size, operationalized as number of beds, and increased work complexity was supported, but the relationship between increased unit size, operationalized as number of nurses, and increased work complexity was not supported. The hypothesized relationship between increased work complexity and increased nurses' participation in decision making was not supported. Work complexity was significantly associated with nurses' participation in decision making but in the opposite direction from that which was hypothesized. The hypothesized relationship between increased nurse participation in decision making and patient ratings of symptom management was not supported. Despite the limitations of the study, this research highlights the importance of the effects of unit size on work complexity for nurses that is often not accounted for when determining nurse staffing in hospitals. This study also illustrates the important effects of work complexity on nurses' ability to participate in decision making on nursing units. Nurses' participation in decision making was found to be significantly negatively impacted by increasing work complexity which reinforces the importance of nurse leaders' facilitation of work conditions that support nurses' full participation in decisions on nursing units. Finally, this study provides support for continued research to identify organizational contexts and structures that foster the delivery of hospital care that is consonant with patients' expectation...