Faecal specimens randomly taken from 232 healthy dogs living in the area of Thessaloniki were screened for internal parasites. In 39·2% of the examined dogs excretion of Sarcocystis bovicanis (1·3%), Isospora ohioensis/burrowsi (3·9%), Giardia lamblia (0·8%), Hammondia heydorni (0·4%), Dicrocoelium dendriticum (0·8%) Diplopylidium nolleri (0·4%), Joyeuxiella pasqualei (0·8%), taeniids (0·4%), Toxocara canis (22·4%), Toxascaris leonina (1·3%), Uncinaria stenocephala (3·0%), Trichuris vulpis (2·6%), Spirocerca lupi (0·4%), or Linguatula serrata (0·4%) was detected. The overall rate of infection did not show any significant difference concerning sex or age. T. canis, however, was significantly more often found in the youngest age group (1–3 months).