Life with Derek is a Canadian sitcom that is currently being aired on the Family channel in Canada (English), on VRAK.TV in Quebec (French), in Germany, Israel, France, Disney Channel in the United States.

Life with Derek is a Canadian sitcom that is currently being aired on the Family channel in Canada (English), on VRAK.TV in Quebec (French), in Germany, Israel, France, Disney Channel in the United States, Mexico, Italy, Portugal, Central America, and South America, Asia, Nickelodeon in Australia and Boomerang in the United Kingdom. It is currently in its 3rd season, and is expected to be produced until at least 2009.

A divorced man named George Venturi who has custody of his two sons, Derek and Edwin and daughter Marti, marries a divorced woman, Nora, with two daughters, Casey and Lizzie.

Up until that point, Casey MacDonald was perfectly content with her life. Growing up as the oldest child in a household with only her mother and sister had suited her well and brought her up as a self-sufficient and independent young woman.

With the addition of a stepfather, two stepbrothers, a stepsister, new school, new house and overall a whole new life, Casey struggles to find her place within the new family. The series is also based on Casey and Derek's rivalry.

The family is revealed to live in London, Ontario when George is reading a newspaper titled "London Chronicle" in episode "Don't Take a Tip From Me." Also in another episode, he refers to himself as "George from London".

Prior to becoming members of a blended family, Casey and Derek were firmly comfortable in their roles as first-born children, including having a major influence on how family decisions were made. When their families blend, each strives for dominance: Casey by "sticking to the rules" and Derek by asserting himself with both force and manipulation. This is further complicated because Derek and Casey are in the same grade in high school; the situation is harder for Casey, who's making new friends. Both teens aren't afraid to speak their minds, especially when trying to recruit their respective parents to be on their side.

The sibling rivalry grows intense at times, and causes them to constantly try to one up the other in order to get their way, even if it involves them getting really sneaky and have to risk being grounded by the adults, and sometimes no matter who gets in the way, whether it's friends or family. In their struggle to find their place, both at home and at school, Casey learns to "loosen up" and break a rule or two, while Derek learns to occasionally "walk the straight and narrow" and put family interests ahead of his own gain, even if it means that Casey benefits.

The show includes several cut-scenes, where various members of the family (usually the ones involved in a problem) interact with one another in a way that is symbolic of their current issue, performed in a nondescript setting with no background.

Despite Casey and Derek's constant bickering and disagreements, they have been known to come together to cooperate toward a common goal, or to use one another to further their own selfish agendas. Although the rivalry continues, they sometimes try to help each other in the series.