Recent advances in analytical (combinatorial chemistry, QSAR, metabolomics), biochemical (proteomics), and molecular (genomics, transcriptomics) technologies are creating an explosion of information on the biology of living organisms.  Table 1 lists the molecular targets, methodology, and names of some techniques that are used to obtain this information. 
    These approaches are being exploited for herbicide discovery and screening in a number of ways.  Our discussion will be divided into two parts, with the first part describing technologies that improve and expand chemical synthesis abilities, and the second part explaining how the ‘-omics’ revolution is facilitating target-based herbicide discovery.

Molecular Target	Genes	mRNAs	Proteins	Metabolites	Whole Plant
Methodology	Generate mutants Screen for reduced growth Identify responsible gene(s)	Extract mRNA Conduct cDNA microarrays Profile gene expression patterns	Extract proteins Conduct 2D gel electro-phoresis Profile protein patterns	Extract metabolites Identify w/ GC or LC/MS Profile metabolite patterns	Conduct bioassays w/ several species Profile physiology
Name	Functional genomics	Transcriptomics	Proteomics	Metabolomics	Physionomics