This chapter focuses on developmental disturbances, challenged child and implications for nursing. This chapter covers the developmental delay and behavior disorder. Each child develops at his or her own pace and the range of normal is quite wide. Developmental delay is when the child does not reach their developmental milestones at the expected times. However, it is helpful to be aware of red flags for potential developmental delays in children. These delays are significant lags in one or more areas of emotional, mental, or physical growth. Attention deficit hyperactivity disorder (ADHD) is a long-term chronic condition that affects millions of children and can continue into adulthood. Nevertheless, ADHD is one of the most commonly diagnosed childhood disorders and is diagnosed much more often in boys than in girls.