An advanced originally designed STM unit combined with a high-resolution SEM to obtain simultaneous STM and SEM images has been developed. High-quality STM parameters have been achieved as a result of the compact size of the unit mounted on the SEM goniometer without any additional vibration isolation. The basis of the STM unit is a 3-coordinate piezowalker which provides coarse and fine tip-to-specimen approach and lateral specimen movement in a 1.5 x 1.5 x 2.5 mm3 range at any SEM goniometer position. The shortest specimen-objective lens distance is 4 mm. Some results of simultaneous studies obtained with a Hitachi S-2500 SEM are presented.