See generally:
Article on Maintenance
New York Spousal Support
New York Spousal Support- Modification
New York: Spousal Support - Frequently Asked Questions

Alimony is payment made by one party to the other after the divorce, either by court order or by mutual agreement. This type of post-divorce payment is also sometimes referred to as maintenance. Until 1980, there were no provisions under New York law for alimony. The Divorce Code of 1980 provides that the court may allow alimony to either party "only if it finds that alimony is necessary."

Under New York law, married people are financially responsible for each other — the husband has a duty to support his wife, and the wife has a duty to support her husband. This duty lasts until the final Decree in Divorce is granted. It doesn't stop simply because the couple separates. Once the parties file for divorce, they must wait at least one year before the final Decree in Divorce is granted. During this period, an agreement on support payments may be appropriate if the parties are separated.

New York laws allow the court to order alimony to a dependent spouse, in such amount as justice requires, if the dependent spouse lacks sufficient property and income to provide for his or her reasonable needs, and if the other party has sufficient property or income to provide for the reasonable needs of the other. In determining the amount and duration of maintenance the court shall consider:

(1) the income and property of the respective parties including marital property distributed in the divorce;

(2) the duration of the marriage and the age and health of both parties;

(3) the present and future earning capacity of both parties;

(4) the ability of the party seeking alimony to become self-supporting and, if applicable, the period of time and training needed to become self-supporting;

(5) reduced or lost lifetime earning capacity of the party seeking alimony as a result of having foregone or delayed education, training, employment, or career opportunities during the marriage;

(6) the presence of children of the marriage in the respective homes of the parties;

(7) the tax consequences to each party;

(8) contributions and services of the party seeking alimony as a spouse, parent, wage earner and homemaker, and to the career or career potential of the other party;

(9) the wasteful dissipation of marital property by either spouse;

(10) any transfer or encumbrance made in contemplation of a matrimonial action without fair consideration;

(11) the standard of living of the parties established during the marriage; and

(12) any other factor which the court shall expressly find to be just and proper.

The court may award permanent alimony, but an award of alimony terminates upon the death of either party or upon the recipient's remarriage.

-From Article 13-236B of the New York Consolidated Laws.