self.lstFiles.grid(row=1, column=0, columnspan=2) buttonFrame = tk.Frame(self) buttonFrame.grid(row=2, column=2, sticky='ew') self.btnAdd = tk.Button(buttonFrame, text="Add...", command=self.addFiles) self.btnAdd.grid(row=0, column=0, sticky='ew') self.btnRemove = tk.Button(buttonFrame, text="Remove", command=self.removeFiles) self.btnRemove.grid(row=0, column=1, sticky='ew')