This is a great combination as both of you are passionate and love adventure and freedom. As long as the relationship incorporates new vistas, countries or learning, you will thrive in this relationship. Aries may tend to want to take the lead in the relationship and Sagittarius is adaptable enough to go along with that. Too much reality, work or unhappiness can burden both and your essential spirit can be lost. Both of you will be willing to be inventive and adventurous in the relationship and so you may bring others in to heighten the interest in the relationship at times when it is low. This should go well as long as you both spend enough time together to develop the connection.