What makes SONG unique? The current measurement precision has now reached a level which makes it possible to obtain data from other stars in a quality similar to the measurements of the Sun. During the last 5 years the techniques used for measuring very precise radial velocities of stars have advanced to a very high level, resulting in the routine detection of solar-like oscillations and discovery of one new planet with the approximate mass of Jupiter every month. Typically these instruments, which are able to measure these very precise velocities, are installed at the world's largest telescopes and operating individually, without participating in any coordinated network observations. Since the main targets are bright stars, which do not require the light collecting area of the large telescopes, the important point for SONG is to have a highly efficient and optimised instrument. This can gain large factors of efficiency, compared to the instruments at large telescopes which are aimed for a larger flexibility. SONG will have a number of unique capabilities/characteristics: Network: Continuous, long-term observations. Not available today. Bright stars: Small telescopes, lower construction and maintenance costs Multiple telescopes per site: High flexibility, multiple targets and control of systematics Instrument: It is less complicated and cheaper to build highly efficient instruments for small telescopes than for a large telescope. Science SONG provides a synergy between asteroseismology and planet search, since a better understanding of the asteroseismic properties of stars is essential for detecting the lowest mass planets. SONG will provide oscillation data for stars of comparable quality to that available for the Sun. Such data do at present not exist. In fact, for the brightest targets the limiting factor for SONG is not the measurement precision but the stellar noise caused by the granulation. By using radial velocity variations to observe oscillations, we gain sensitivity to modes of oscillation which are not measurable with light intensity variations. These oscillation modes provide more precise determinations of the conditions near the stellar core where most of the energy generation takes place. Because long, continuous observations will be obtained with SONG, no existing single site facility, irrespective of telescope size and measurement precision, can compete. Only a network with more nodes and larger telescopes could outperform SONG, i.e. a super-SONG.