The nearby, bright, and compact radio sources can be put into the context of the radio source population by considering the following.
The sample of 1 Jy extragalactic radio sources [Stickel, Meisenheimer, & Kühr 1994] contains 527 sources with 5 GHz flux densities greater than 1 Jy and 
. Of these sources 71/527 lie at red shifts less than z=0.06. At z=0.06, 1 mas is approximately equivalent to 1 pc at the source, assuming a Hubble constant of 75 km/s/Mpc. Thus, VLBI observations of sources below this red shift allow sub-pc-scale spatial resolution radio imaging
17/71 of these nearby sources are listed by Stickel, Meisenheimer, & Kühr [1994] as having flat radio spectra; they are good candidates for being sources with flux densities in excess of 1 Jy at VLBI resolution ( 
Jy) since flat-spectrum sources are likely to be core dominated.
On the other hand, 54/71 of the nearby sources are listed as having steep radio spectra. These sources are not good candidates for Jy since they are likely to be lobe dominated radio galaxies. To select Jy sources from these 54 objects, core dominance parameters of R<0.33 (ratio of core to extended flux density) were adopted. Thus, steep-spectrum radio sources with a total flux density > 4 Jy became candidates for Jy. For example, R=0.33 and 
Jy corresponds to 
Jy; lower values of R are possible for higher values of 
, but it is unlikely that higher values of R (i.e. lower values of ) are appropriate for lobe dominated sources. 12/54 of the nearby steep-spectrum sources listed by Stickel, Meisenheimer, & Kühr [1994] have 
Jy.
Thus, 29 of the 527 sources in the 1 Jy sample are candidates for Jy and z < 0.06. A search of the literature was performed for these 29 sources and it was found that 12/29 could unambiguously be shown to have Jy. These 12 sources consisted of 8/17 of the flat-spectrum sources and 4/12 of the steep-spectrum sources, making up a ``Whole-Sky'' sample. In support of the selection criteria for the steep-spectrum sources given above, the 4/12 steep-spectrum sources found to have Jy have of 681 Jy, 120 Jy, 15 Jy, and 12 Jy, all well above the lower limit of 4 Jy.
Six of the 12 ``Whole-Sky'' sources were selected for study, those sources south of 
, over a period of three years with multi epoch and multi frequency VLBI observations. Those six sources are listed in Table 1.1.
Additional sources have been studied during the course of this thesis, namely sources used in the comparison between the VLBI properties of EGRET-identified radio sources and the VLBI properties of similar sources which have not been identified by EGRET. The sources included in the thesis for this purpose are listed in Table 1.2 and their selection is discussed in chapter 4.
Finally, one more source was (unexpectedly, but happily) added to the scope of this thesis. The radio source associated with the Galactic X-ray nova GRO J1655-40 was discovered in 1994 August and subsequently investigated over a period of four days with the SHEVE array. These observations provided the unique opportunity for a very high spatial resolution view of a rapidly evolving, relativistic Galactic jet.
Table 1.1: Six low red shift radio sources
Table 1.2: Gamma-ray loud and quiet radio sources