Hi! All I am trying to merge very large data sets. Here fullset1 contains 13 data sets. Each data set has columns which I need to merge. Here I am trying to merge columns 2,6,10,14....till end for all 13 data sets in fullset1. But I am only getting 2nd column here. Rchan1 = sapply(1:length(fullset1), function(i) exprs(fullset1[[i]])[ ,2]) Rch1 = as.list(Rchan1) red1 = do.call(cbind,Rch1) Likewise, here I need to merge columns 3,7,11,15...till end for all 13 data sets in fullset1. And I am getting 3rd column only. Gchan1 = sapply(1:length(fullset1), function(i) exprs(fullset1[[i]])[ ,3]) Gch1 = as.list(Gchan1) green1 = do.call(cbind,Gch1) I am stuck! Please Help! Cheers! Amit