Abstract: Epitachophoresis (ETP) methods and devices that improve concentrating samples and/or separating components of samples. ETP methods and devices allow for electromigration in two dimensions. Electromigration of a sample may first occur in a first dimension along a single plane. Electromigration may then continue in a second dimension, which may be different from the first dimension. The volume where the electromigration occurs may significantly reduce from the first dimension to the second dimension. This smaller dimension may allow for increased concentration of samples or improved separation of components of a sample.