More then one billion people in the world lack access to clean water, and things are getting worse. Read Nature's analysis of the global water crisis with a collection of news, features and interactive graphics.

Today, just four countries account for 99% of the world's commercially grown transgenic crops. Others have been stalling over whether to embrace transgenic agriculture, but won't be able to put off the decision much longer. Here, Natureexamines the state of play with special features and interactive graphics.

Malaria continues to claim a significant number of lives worldwide, estimated at ~ 1 million each year. The genome sequence of the most prominent human parasite, Plasmodium falciparum, was published inNaturein 2002. We are now proud to present the genome sequences of two additional human parasites,Plasmodium vivaxandPlasmodium knowlesi, along with a Review article discussing the scientific discoveries that have been aided by this information. In addition, we present a collection of papers illustrating highlights in malaria research that were published in recent years.

Analyses of microbial genomes both at the level of a single species genome and at the community metagenome level have been providing many novel insights into microbial life and the impacts on its environment. This web focus presents a collection of recent studies on important human and plant pathogens, ocean microbes, the human microbiome, plant and animal symbionts, and environmental microbial communities.

Every 26 months, Mars and Earth come into an alignment that minimises the fuel needed to journey between the two. Summer 2003, three new spacecraft took off. Nature introduces these missions with interactive graphics and features on the red planet.

As the number of human beings with their genomes fully sequenced ticks higher and direct-to-consumer gene profiling companies push the limits of what medical genetics can do, the once fantastical notion that any given human can walk into a doctor's office with her genome on a hard drive looks more and more like a reality. Still the question remains to be answered: how do we use this wealth information? In this Natureweb focus we proudly present the challenges this approaching reality poses for technology, the legal and ethical confines of research, and the ability of genomics to translate into clinical utility. Here you'll also find the latest additions to the human genome menagerie, males from Africa and Asia.

Life depends on relationships. The enormous technological progress achieved in recent years has made it possible to investigate the 'simple' one-on-one interactions between two species as well as defining the associations between complex microbial communities and humans. These effortshave provided insights reaching from the identification of the participating partners to defining beneficial molecular and cellular interactions. This web focus both reflects the broad scope of symbiosis research and demonstrates how similar the underlying concepts are, independent of the system investigated. It is certainly a fascinating and fast-moving field, as we hope is portrayed in this selection of papers.

Immigration controls introduced under the 'war on terror' are restricting the flow of foreign researchers into the US. With other countries moving in on this pool of talent, will the balance of scientific power shift? Read our special report from the Naturenews team.

The electrical potential across cellular membranes is sensed by specialized proteins — typically, voltage-gated ion channels. Until recently, the mechanism by which 'voltage sensors' respond to potential changes was unclear. But since the first, and very surprising, structure of a voltage-sensing domain 5 years ago, much progress has been made. This focus celebrates the twists and turns of that progress in an archive of Naturepapers from the past 5 years.

This year marks the 25th anniversary of two papers reporting the first isolation of mouse ES cells. The first impact of the mouse ES papers was enabling targeted gene knock outs in mice, which has revolutionized mouse genetics and developmental biology. Seventeen years later, Jamie Thomson isolated ES cells from human embryos, a technical achievement that has become of the great milestones in human biomedical research. To mark this occasion, Natureis featuring papers that show the progression of ES cell research. We hope you find it a compelling story.

The development of new antimicrobial drugs is urgently needed in the battle against infectious diseases. The discovery of a new antimicrobial — platensimycin — represents a previously unknown class of antibiotics. This Nature web focus features the latest on this discovery and includes a News & Views article, and specially selected papers on antibiotic function, resistance and development.

Brain-machine interfaces promise to aid paralyzed patients by re-routing movement-related signals around damaged parts of the nervous system. A new study in Naturedemonstrates a human with spinal injury manipulating a screen cursor and robotic devices by thought alone. Implanted electrodes in his motor cortex recorded neural activity, and translated it into movement commands. A second study, in monkeys, shows that brain-machine interfaces can operate at high speed, greatly increasing their clinical potential. ThisNatureWeb Focus includes exclusive interviews and video footage of experiments, alongside papers that paved the way for these recent advances.