She doesn't really need a previous work experience to get the open work permit. Completing an advanced degree is enough. "Open" work permit means she will get a work permit that is not tied to any particular industry/expertise/profession. She can work as a cashier in MacDonald's or as a Financial Services Advisor in CIBC- there's no limit to what she can do. As for proof of relationship, include your marriage certificate and if possible, wedding pictures and other pictures of you two together at various times. What is needed is the marriage certificate. The others are just little extras to strengthen your application. The letter of explanation should include (a) a letter written, dated and signed by her which states that she needs the work permit to be with you in Canada and work to support you. The letter should mention your name and occupation, the amount of money in the bank statement of account you will submit as part of the application and most importantly, her ties to your home country. (b) A letter of support written by you, signed and dated which confirms that she will be going to Canada with your support and that you will take care of her financial needs until she is able to find work. Some people also recommend that this letter be notarized. Your letter should also include specifics of your job, your contact phone numbers (Mobile, Home, Work), your e-mail address, so that they can contact you if they want. (c ) Your letter of employment showing how much you earn (d) Your bank statement (e) Your own work permit and Visa (f) Ties to your country such as lands/houses bought in her name (g) and any other thing you wish to explain regarding her application. All these can be combined in one PDF document. Good luck!