Federal agencies are required to prepare a strategic plan every three years that describes plans and goals for at least five years into the future. NASA's Office of Space Science (OSS), which supports about three-quarters of American astronomy, recently published its latest strategic plan, which goes even further and summarizes priority science goals and mission concepts that may take at least two decades to realize. This talk will summarize the scientific and mission priorities for OSS for the early part of this century, plus discuss the evolving vision for human spaceflight in the years after completion of the International Space Station.