The technique and results of synovectomy of the shoulder joint in rheumatoid arthritis with a mean follow up time of 5.3 years (1-16 years) is described. The original method included resection of acromion after loosening of the deltoid muscle and splitting of the rotator cuff. Since 1981 the simpler approach of Neer without resection of acromion has been used (for synovectomy as well as for prosthetic replacement) with an easier postoperative management and equally good results. Only in 6 of 54 shoulders a total replacement prosthesis has been inserted later, an indication of the lasting good effect of synovectomy, even in advanced cases where an additional debridement was necessary. The best results are obtained in early cases. Radiographic changes are late, indications should be based more on clinical findings. Access to good training facilities is mandatory.