This dissertation addresses gaps in the child welfare literature from a systemic perspective. The extant literature focuses primarily on children in care, which excludes 90% of children and families involved with the system. In addition, foster parent retention has become an area of primary concern because there are fewer individuals who are willing to foster. Research that examines all children involved with the child welfare system and ways to improve foster parent experiences is imperative to address these areas of need. The two studies herein address these gaps in the literature by examining children who are in contact with the child welfare system but largely remain out of care, children who are in care, and foster caregivers. The first study compared two groups of children in the Ontario child welfare system: those who remain with their natural family and those in out-of-home care. The emotional and behavioural functioning, prosocial behaviour, education, health, and resources (internal and external) of these two groups of children were examined and relatively few significant differences were identified. However, it was found that, despite having comparable mental health and educational functioning, children who remained in their natural homes had significantly fewer external resources than children in out-of-home care. Children in out-of-home care may have increased access to community resources despite having similar needs to children who remain in their natural home environments. Additional research is needed to replicate and better understand these findings so that the child welfare system can best meet the needs of its children. The second study examined how foster child characteristics, as well as other foster parent and agency factors, impact Canadian foster parents' experience of fostering, particularly related to agency workers, the fostering system, training, and foster children and their placements. Results identified that foster children's needs and maltreatment histories, as reported by foster parents, were not significantly associated with perceptions about fostering. The factors that were the most highly associated with positive perceptions about fostering were increased practical and emotional support. These findings indicate that child welfare agencies can improve foster parents perceptions about fostering by providing sufficient practical and emotional support. A monitoring system that allows foster parents to provide regular feedback would be beneficial in continuing to evaluate their fostering experiences, assess the impact of interventions targeting foster parent support, and address any areas of concern. As a whole, the results of this dissertation highlight the importance of providing both children and foster parents in the child welfare system with appropriate supports that promote positive child functioning and foster parent experiences.