The assignment of authorship becomes an important issue since the modern scientific researches need more and more collaborative work than the past ones. The average number of authors for the articles has increased obviously since 1925 (http://www.nap.edu/readingroom/books/obas/contents/authorship.html). Authorship credit and authorship order are quite important to personal scholarly reputation, promotion, salary and grant seeking, therefore, they should be dealt with ethics and caution.
Authorship is defined as an author who has made a substantial, direct, intellectual contribution to the work and has participated in writing the manuscript either by primary writer or reviewing the draft to the final version (http://hms.harvardedu/integrity/authorship.html). So anyone who does not make a substantial, direct, intellectual contribution to the researches should not deserved authorship; even the chair of the institute is no exception. Surely there are many persons involved in the studies, such as technical assistance, supplying study materials, grant support for researches; they should be on the list of acknowledgement in stead of the author list.
The assignment of authorship and authorship order should be discussed open, frank and clearly at the very beginning of the research paper be done. Study participants should define their obligation and contribution to the work, and try to get the agreement of authorship with each other. All the contribution of each member must be recorded and proven by every author before the paper is published. If dispute of authorship happens, they could consult the mutual-trusted third party to sought better solutions. However, if the solution proposed by the third party can not satisfy all the members, the superior directors should come up a result by detecting their direct, intellectual contribution to the work. Authorship means not only an honor, a credit of academic field, but also a responsibility and commitment to what you have done in the past, now and future.