Application scientists face a challenge -- the need to analyze and understand ever larger and complex datasets grows more acute on a daily basis, yet visualization and analysis technology and interactive resources have not evolved at a pace similar to scientific simulations and centralized computing facilities. Our vision is to respond to the needs of the science applications community by providing, through close collaborative research, domain-specific tools that answer the challenges posed by large and complex data. Our response consists of two broad thrust areas. First, fundamental research in visualization algorithms provides solutions tailored to specific domain challenges. Second, research in visualization architectures and deployment mechanisms helps to make advanced visualization technology accessible to domain scientists.