I am new here and new to Modelbuilder. I have been trying to create a toolbox. I have managed to branch down the tool into simple models in Modelbuilder but in most cases I can not combine my models together. I mean, they models work properly in separate models but I can not find a way to have them all in one model. Sometimes it is impossible to join them together and sometimes it doesn't work properly. I was wondering what is the best way to combine them together. should I convert all the models to script and then combine them together and use the tool as a script or there is a way to export/import the models. Thank you all in advance for helping me on this.