Minimal invasive neurosurgery is becoming more and more standard in neurosurgical procedures. Several types of lesions are now approached endoscopically. The surgical planning and intraoperative orientation during endoscopic surgical procedures are sometimes difficult. To solve this problem, a combination of the endoscopic procedure with a frameless, armless neuronavigation system is used in our service. The combination of the endoscope and the frameless navigation system was used in tumour surgery, ventriculostomies and arachnoid cyst operations. All procedures were performed successfully. The combination of both systems has proved to be advantageous because of safe surgical planning using the frameless stereotactic technique and the possibility of real time orientation of the endoscope. This technique is very useful in removing intraventricular and large brain mass lesions.