W20 Nucleic Acids Research, 2009, Vol. 37, Web Server issue Figure 2. Usage of the HMS on the Web. Input source IDs in the textbox, and select the type of IDs. Then, select database to open, and push the ‘Search’ button. Then, the HMS searches for IDs that correspond to the source IDs and opens pages of destination databases. If there are two or more corresponding data, the HMS shows the list of IDs with hyperlinks. This ﬁgure shows an example of opening Locus view of H-InvDB with an accession number BC053657. Research (1). The number of databases is increasing every year. Because biologists usually wish to combine a certain type of data with another, integration of these various and huge databases will be of great signiﬁcance. In principle, there are two possible ways of integrating databases. One is to collect all the databases at one place and merge them, while the other is to combine the databases virtually by hyperlinking corresponding data among them. The former method requires an enormous amount of disk space of computers and a large number of people to main- tain and update the databases. In other words, the cost of the former method is too large to implement. In fact, there was an attempt to construct a huge integrated database of many biological data by the former method, which failed in a few years probably due to the high running cost. The latter method, on the other hand, can be realized rel- atively easily if we adopt the automated hyperlinking that we introduced in this article. The HMS will be a funda- mental platform to virtually integrate databases that are operated independently by diﬀerent organizations. Furthermore, the HMS will make it possible for us to construct integrated databases in a sustainable way. The ICS is also a quite useful tool. Because major data- bases such as INSD and UniProt update their ‘live lists’ of