Abstract. Phylogenetic reconstruction based on gene rearrangements is attracting increasing attention from biologists and computer scientists. Methods used in reconstruction include distance-based methods, parsimony methods using sequence encodings, and direct optimization. The latter, pioneered by Sankoff and extended by us with the software suite GRAPPA, is the most accurate approach; however, its exhaustive nature means that it can be applied only to small datasets (of fewer than 15 taxa). While we have successfully scaled it up to 1,000 taxa by integrating it with a disk-covering method, yielding DCM-GRAPPA, the recursive decomposition in the DCM may require many levels of recursion to handle datasets with 1,000 or more taxa. In order to handle larger datasets and reduce the need for recursive decomposition, we investigate quartet-based approaches, which directly decompose the datasets into subsets of four taxa each. Such approaches have been well studied for sequence data, but not for gene-order data. We give an optimization algorithm for the NP-hard problem of computing optimal trees for each quartet, present a variation of the dyadic method (using heuristics to choose suitable short quartets), and use both in simulation studies. We find that our quartet-based method can handle more taxa than the base version of GRAPPA, thus enabling us to reduce the number of levels of recursion in DCM-GRAPPA, but is more sensitive to the rate of evolution, with error rates rapidly increasing when saturation is approached.