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The analysis of a sample for the presence of target analytes is facilitated with a number of sample preparation and instrument techniques. Liquid chromatography coupled with tandem mass spectrometry (tandem quadrupole) (LC-MS/MS) has been largely to thank for a large number of significant analytical methods for target analytes such as pesticides, mycotoxins, drugs, and antibiotics. A crude literature search using the keyword liquid chromatography mass spectrometry revealed more than 52,000 articles on the topic. On the other hand, liquid chromatography time of flight reveals only approximately 2300 articles. The main reason for this difference is arguably due to the recent development of time of flight (TOF) for the purpose of trace analytical determinations as opposed the fairly well-developed LC-MS/MS. In this regard, manual interpretation by the analyst is integral to the success in identification and confirmation of target analytes. Confident interpretation of data from LC-TOF can be developed through an accretion of information from the analytical process: sample extraction and cleanup, chromatographic retention time, mass spectral details such as the closeness of accurate mass of the molecular ion and fragments to those of a predicted target analyte, and finally comparison to authentic standards included in the same analytical process as the unknown. An accurate mass determination is in itself quite important to the tentative identification of an unknown target analyte. In this regard, a close agreement to the true mass of an unknown target analyte results in a smaller range of possible empirical formulae, a point that is well developed in this text. This work summarizes perspectives on (accurate) mass determinations using TOF and qTOF and its use as a tool for the identification and confirmation of target, nontarget, and unknown compounds.