Contemporary adoption practices can be divided into two forms: 1) Open and 2) Closed.

Open adoption allows identifying information to be communicated between adoptive and biological parents and, perhaps, interaction between kin and the adopted person. Rarely, it is the outgrowth of laws that maintain an adoptee's right to unaltered birth certificates and/or adoption records, but such access is not universal (it is possible in a few jurisdictions - including the U.K. and six States in the U.S.). Open adoption can be an informal arrangement subject to termination by adoptive parents who have sole authority over the child. In some jurisdictions, the biological and adoptive parents may enter into a legally-enforceable and binding agreement concerning visitation, exchange of information, or other interaction regarding the child. As of February 2011, 24 U.S. states allowed legally enforceable open adoption contract agreements to be included in the adoption finalization. (Adoption 2011)

The practice of closed adoption, the norm for most of modern history, seals all identifying information, maintaining it as secret and barring disclosure of the adoptive parents', biological kins', and adoptees' identities. Nevertheless, closed adoption, may allow the transmittal of non-identifying information such as medical history and religious and ethnic background. Today, as a result of safe haven laws passed by some U.S. states, closed adoption is seeing renewed influence. In safe-haven states, infants can be left, anonymously, at hospitals, fire departments, or police stations within a few days of birth, a practice criticized by some adoptee advocacy organizations as being retrograde and dangerous. (Adoption 2011)

How adoptions originate

Adoptions can occur either between related family members, or unrelated individuals. Historically, most adoptions occurred within a family, though. The most recent data from the U.S. indicates about half of adoptions are currently between related individuals. A common example of this is a "stepparent adoption", where the new partner of a parent may legally adopt a child from the parent's previous relationship. Intra-family adoption can also occur through surrender, as a result of parental death, or when the child cannot otherwise be cared for and a family member agrees to take over. (Adoption 2011)

Infertility is the main reason parents seek to adopt children they are not related to. One study shows this accounted for 80% of unrelated infant adoptions and half of adoptions through foster care. Estimates suggest that 11%-24% of Americans who cannot conceive or carry to term attempt to build a family through adoption, and that the overall rate of ever-married American women who adopt is about 1.4%. Other reasons people adopt are numerous although not well documented. These may include wanting to cement a new family following divorce or death of one parent, compassion motivated by religious or philosophical conviction, to avoid contributing to perceived overpopulation out of the belief that it is more responsible to care for otherwise parent-less children than to reproduce, to ensure inheritable diseases (e.g., Tay-Sachs disease) are not passed on, and health concerns relating to pregnancy and childbirth. Although there are a range of possible reasons, the most recent study of women who adopt experiences suggests they are most likely to be 40–44 years of age, currently married, have impaired fertility, and childless. (Adoption 2011)

Unrelated adoptions may occur through five mechanisms:
1) Private domestic adoptions: under this arrangement, charities and for-profit organizations act as intermediaries, bringing together prospective adoptive parents and families who want to place a child, all parties being residents of the same country. Alternatively, prospective adoptive parents sometimes avoid intermediaries and solicit pregnant women directly; drafting contracts through a lawyer (this is illegal in some jurisdictions). Private Domestic Adoption accounts for a significant portion of all adoptions; in the United States, for example, nearly 45% of adoptions are estimated to have occurred through private arrangements. (Adoption 2011)

2) Foster care adoption: this is a type of domestic adoption where a child is initially placed in public care. Its importance as an avenue for adoption varies by country. Nevertheless, the example of the United States is instructive. Of the 127,500 adoptions that occurred in the U.S. about 51,000 or 40% were through the foster care system. (Adoption 2011)

3) International adoption: involves the placing of a child for adoption outside that child’s country of birth. This can occur through both public and private agencies. In some countries, such as Sweden, these adoptions account for the majority of cases (see above Table). The U.S. example, however, indicates there is wide variation by country since adoptions from abroad account for less than 15% of its cases. More than 60,000 Russian children have been adopted in the United States since 1992, and between 1995 and 2011, Americans adopted more than 60,000 children from China. The laws of different countries vary in their willingness to allow international adoptions. Recognizing the difficulties and challenges associated with international adoption, and in an effort to protect those involved from the corruption and exploitation which sometimes accompanies it, the Hague Conference on Private International Law developed the Convention on Protection of Children and Co-operation in Respect of Intercountry Adoption, which came into force on 1 May 1995 and has been ratified by 75 countries, to date. (Adoption 2011)

4) Embryo adoption: the state of Georgia in the United States of America is the first jurisdiction to include human embryos in it adoption laws. Conservative evangelicals are the primary supporters, considering it a recognition of embryo life and a mechanism to save that life. These developments in adoption law are not without critics, however, even among religious communities. While the Catholic Church has not announced its support or opposition to the adpotion of embyros, its theologians are divided on the issue with some deeming it a "grave violation of nature," and others viewing it as an act of charity. In the absence of adoption laws, embryo relinquishment has occurred under property laws, being transferred from one set of individuals to another. As of 2003, 400,000 embryos had been frozen in the United States alone and an estimated 2% or 9,000 were available for donation; the rest were reserved for future use by the parents or for medical research. (Adoption 2011)

5) Common law adoption is a phrase used to describe an adoption which has not been recognized, beforehand, by the courts, but where a parent, without resort to any formal legal process, leaves his or her children with a friend or relative for an extended period of time. At the end of a designated term of (voluntary) co-habitation, as witnessed by the public, the adoption is then considered binding, in some courts of law, even though not initially sanctioned by the court. The particular terms of a common-law adoption are defined by each legal jurisdiction. For example, the U.S. state of California recognizes common law relationships after co-habitation of 2 years. (Adoption 2011)