Virginia law, § 20-107.1 of the Code of Virginia (1950, as amended) provides factors to be considered by the court when awarding spousal support, or alimony:

§ 20-107.1. Court may decree as to maintenance and support of spouses.

The court, in determining whether to award support and maintenance for a spouse, shall consider the circumstances and factors which contributed to the dissolution of the marriage. In determining the nature, amount and duration of an award pursuant to this section, the court shall consider the following:

• The obligations, needs and financial resources of the parties, including but not limited to income from all pension, profit sharing or retirement plans, of whatever nature;
• The standard of living established during the marriage;
• The duration of the marriage;
• The age and physical and mental condition of the parties and any special circumstances of the family;
• The extent to which the age, physical or mental condition or special circumstances of any child of the parties would make it appropriate that a party not seek employment outside of the home;
• The contributions, monetary and nonmonetary, of each party to the wellbeing of the family;
• The property interests of the parties, both real and personal, tangible and intangible;
• The provisions made with regard to the marital property during equitable distribution;
• The earning capacity, including the skills, education and training of the parties and the present employment opportunities for persons possessing such earning capacity;
• The opportunity for, ability of, and the time and costs involved for a party to acquire the appropriate education, training and employment to obtain the skills needed to enhance his or her earning ability;
• The decisions regarding employment, career, economics, education and parenting arrangements made by the parties during the marriage and their effect on present and future earning potential, including the length of time one or both of the parties have been absent from the job market;
• The extent to which either party has contributed to the attainment of education, training, career position or profession of the other party; and
• Such other factors, including the tax consequences to each party, as are necessary to consider the equities between the parties.

While the Court will consider all of the above factors, it does not need to mention all of them in its decision, and it can weigh certain factors more heavily than others depending on the facts of the case.
Tax-wise, spousal support generally counts as income for the receiving spouse and is deductible by the paying spouse.