Teamwork is a great SaaS project management solution for small-mid sized companies and project teams. Like other products in this category, Teamwork is focused on task management and collaboration, sacrificing some features and complexity of enterprise solutions, for ease of use.
Tasks and task lists are at the core of Teamwork. Within a project, Project Managers create and assign tasks. Team members can review their tasks; add comments, track time, and mark tasks as complete. Tasks can also be associated with project milestones. A calendar view of project milestones gives a nice high-level overview of important project dates.