Vo lume 13  Sp e c ia l Issue Jo urna l o f the Asso c ia tio n fo r Info rm a tio n A b stra c t Sp e c ia l Issue And re a s Sc hm e il Unive rsità d e lla Svizze ra Ita lia na (USI) a nd re a s.sc hme il@ usi.c h Ma rtin J. Epp le r Unive rsity o f St. G a lle n m a rtin.e p p le r@ unisg .c h Sa ra d e Fre ita s C o ve ntry Unive rsity sfre ita s@ c a d .c o ve ntry.a c .uk While 3D virtua l wo rld s a re mo re fre q ue ntly b e ing use d a s inte ra c tive e nviro nm e nts fo r c o lla b o ra tio n, the re is still no struc ture d a p p ro a c h d e ve lo p e d sp e c ific a lly fo r the c o m b ine d d e sig n o f 3D virtua l e nviro nm e nts a nd the c o llab o rative ac tivitie s in the m. We arg ue that fo rmalizing bo th the struc tural e le me nts o f virtual wo rlds and a sp e c ts o f c o lla b o ra tive wo rk o r c o lla b o ra tive le a rning he lp s to d e ve lo p fruitful c o lla b o ra tive wo rk a nd le a rning e xp e rie nc e s. As suc h, we p re se nt the a va ta r-b a se d c o lla b o ra tio n fra m e wo rk (ABC fra m e wo rk). Ba se d o n se mio tic s the o ry, the fra me wo rk p uts the c o lla b o ra ting g ro up s into the c e nte r o f the de sig n a nd e mp ha size s the use o f d istinc t fe a ture s o f 3D virtua l wo rld s fo r use in c o lla b o ra tive le a rning e nviro nm e nts a nd a c tivitie s. In d e ve lo p ing the fra m e wo rk, we ha ve d ra wn fro m b e st p ra c tic e s in instruc tio na l d e sig n a nd g a m e d e sig n, re se a rc h in HC I, a nd find ing s a nd o b se rva tio ns fro m o ur o wn e m p iric a l re se a rc h tha t inve stig a te s c o lla b o ra tio n p a tte rns in virtua l wo rlds. Alo ng with the fra m e wo rk, we p re se nt a c a se stud y o f its first a p p lic a tio n fo r a g lo b a l c o lla b o ra tive le a rning p ro je c t. This p a p e r p a rtic ula rly a d d re sse s virtua l wo rld d e sig ne rs, e d uc a to rs, m e e ting fa c ilita to rs, a nd o the r p ra c titio ne rs b y tho ro ug hly d e sc rib ing the p ro c e ss o f c re a ting ric h c o lla b o ra tio n a nd c o lla b o ra tive le a rning e xp e rie nc e s fo r virtua l wo rld s with the ABC fra m e wo rk. Ke y wo rds: G ro up C o lla b o ra tio n, C o lla b o ra tio n Pa tte rns, Em b o d ie d C o lla b o ra tio n, Pre se nc e , Virtua l Wo rld s, De sig n Sc ie nc e Re se a rc h, O nline C o lla b o ra tio n, Im m e rsio n. Vo lume 13, Sp e c ia l Issue , p p . 836-860, O c to b e r 2012 A Struc ture d A p p ro a c h fo r De sig ning C o lla b o ra tio n Exp e rie nc e s fo r Virtua l Wo rld s * G e rt Ja n d e Vre e d e w a s the a c c e p ting se nio r e d ito r. This a rtic le w a s sub m itte d o n 15 th De c e mb e r 2010 a nd w e nt thro ug h tw o re visio ns.