We report the results of the analysis of high resolution photospheric line spectra obtained with the UVES instrument on the VLT for a sample of 15 solar-type stars selected from a recent survey of the distribution of H and K chromospheric line strengths in the solar-age open cluster M67 .
 We find upper limits to the projected rotation velocities that are consistent with solar-like rotation ( i.e. , v \sin { i } \lesssim 2–3 km s ^ { -1 } ) for objects with Ca II chromospheric activity within the range of the contemporary solar cycle .
Two solar-type stars in our sample exhibit chromospheric emission well in excess of even solar maximum values .
In one case , Sanders 1452 , we measure a minimum rotational velocity of v \sin { i } = 4 \pm 0.5 km s ^ { -1 } , or over twice the solar equatorial rotational velocity .
The other star with enhanced activity , Sanders 747 , is a spectroscopic binary .
 We conclude that high activity in solar-type stars in M67 that exceeds solar levels is likely due to more rapid rotation rather than an excursion in solar-like activity cycles to unusually high levels .
 We estimate an upper limit of 0.2 % for the range of brightness changes occurring as a result of chromospheric activity in solar-type stars and , by inference , in the Sun itself .
We discuss possible implications for our understanding of angular momentum evolution in solar-type stars , and we tentatively attribute the rapid rotation in Sanders 1452 to a reduced braking efficiency .