1. The defendant's appeal and the plaintiff's incidental appeal are all dismissed.

2. Costs arising from an appeal and an incidental appeal shall be respectively.

1. Basic facts

A. The relationship 1) The Defendant is an organization established pursuant to the Act on the Establishment and Operation of Public Interest Corporations (hereinafter “Defendant”) for the purpose of developing performing arts through the joint performance on January 31, 200 and fostering performing art human resources through the joint performance on January 31, 200.

(2) On January 1, 2003, the Plaintiff joined the Defendant choir and served as a member (theme). From November 12, 2007, the Plaintiff served as the head of the branch of the “C” organized by the Defendant’s employees (hereinafter “Defendant trade union”).

3) On December 31, 2013, the Plaintiff entered into a member’s labor contract with the Defendant “the Plaintiff shall work as a member of the Defendant choir from January 1, 2014 to December 31 of the same year.” The written labor contract was written as “the Plaintiff shall maintain his/her dignity as a member of the Defendant choir and comply with the members’ operating regulations and the members’ service regulations” (Article 3(1)), and “the Plaintiff shall not concurrently perform other duties except where prior approval is obtained, and shall obtain prior approval from the artistic supervisor in the event of performing other performance than the performance under the Defendant’s supervision (Article 3(3)). On the same day, the Plaintiff submitted to the Defendant a written commitment with the content that “the Plaintiff shall not engage in any artistic activity other than the Defendant’s jurisdiction, and shall make a contribution after obtaining prior approval from the artistic supervisor upon the outside performance.”

(2) Around October 23, 2014, the Defendant’s member demanded a resolution on disciplinary action against the Plaintiff on the ground that he/she contributed to an external performance, other than the Defendant’s performance, on the ground that he/she contributed to the external performance without the approval of the artistic supervisor.

On December 2, 2014, the Defendant violated Article 6 of the Members Service Rules to the Plaintiff.